a: 3 ' £ 
 
 U. S. DEPARTMENT OF AGRICULTURE. 
 
 division of entomology. 
 
 Bulletin No. 3. 
 
 REPORT 
 
 OF 
 
 OBSERVATIONS AND E 
 
 IX 
 
 THE PRACTICAL WORK OF THE DIVISION, 
 
 UNDER THE DIRECTION O^flE ENTOMOLOGIST. 
 
 WITH PLATES 
 
 5135 
 
 WASHINGTON: 
 
 GOVERNMENT PRINT ING .OFFICE. 
 
 1883. 
 
PREFACE. 
 
 This Bulletin contains some recent notes on the Army Worm, espe- 
 cially with reference to its food-plants and to its injuries in the cranberry 
 bogs of New Jersey during the summer of 1882, such injury by this in- 
 sect not having been previously recorded. There are some additional 
 experiments with pyrethruin, with a view of ascertaining its effect on 
 different insects, and some notes on insects injurious to forest trees. 
 All these notes were prepared for the Annual Report, but were neces- 
 sarily excluded for want of space. 
 
 A report by Dr. E. H. Anderson of observations on the Cotton Worm 
 the present summer in Southern Texas will prove interesting, as show- 
 ing what is being done in that section, and as illustrative of the per- 
 sistence of false theories long after they have been exploded. In his 
 correspondence and earlier reports Dr. Anderson has always held to 
 the view that the pupa of Aletia hibernates, and he has given in this 
 report the testimony of several planters to that effect. We publish his 
 report as it was written, as this is our rule in such cases, but we wish 
 the reader to remember that the hibernation of the chrysalis has been 
 definitely disproven, and that it is now an established fact that hiber- 
 nation takes place in the moth state, and that the pupae which fail to 
 give forth the moth before severe frost invariably perish. 
 
 The machine described and illustrated in our last Annual Report for 
 spraying cotton from below had been perfected to a large extent with- 
 out accurate field test of its practical working. We very much desired, 
 therefore, to learn whether any improvements could be made in its 
 several parts or what faults it possessed as a working machine, and as 
 soon as news came that the worms had begun to work around Selma, 
 Ala., Dr. Barnard was sent down with the instructions which accom- 
 pany his report. The advantages of the machine, and they are many, 
 have already been set forth in the Annual Report for 1881-'82; but the 
 report of Dr. Barnard would seem to show that considerable modifica- 
 tion in the details, especially of attachment, is necessary. Future ex- 
 perience may lead to the abandonment of the attempt to spray cotton 
 from the ground up, on account of the irregularity of the rows in the 
 average cotton-field, and the adoption of lateral or oblique spraying 
 from nozzles that do not drag entirely on the ground, but hang some 
 iuches above it. The objection which the average cotton-field offers 
 will not hold so strongly in case of a crop of potatoes, where the plants 
 are much lower and in much more uniformly-spaced rows. The results 
 of Dr. Barnard's further experiments show that the objections to the 
 
8 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 stiff connection, for the reasons set forth, may be overcome when in the 
 cotton-field. 
 
 The late Dr. James S. Bailey,* of Albany, N. Y., was commissioned 
 some time ago to prepare a full account for publication by the Depart- 
 ment of the wood-boring lepidopterous larvae of the family Cossidae, as he 
 had given much attention to this group and was familiar with all of the 
 North American species. It was his intention to have prepared such 
 an article, giving particular attention to life-habits. Unfortunately his 
 health from the period of his instructions to his recent death was such 
 that he was unable to fully carry out the plan, and we furnish the re- 
 port incomplete and falling short of what it would have been had he 
 lived. We publish it as it was written, and do not desire to be held re- 
 sponsible for his views. The principal species discussed, Cossus center- 
 ensis, was first described by Mr. J. A. Lintner in the Canadian Ento- 
 mologist for July, 1877, where many of the facts were given that were 
 detailed by Dr. Bailey in a later article in the same periodical for Jan- 
 uary, 1879, and in the report here published. 
 
 This Bulletin concludes with a report by Dr. William McMurtrie, pro- 
 fessor of chemistry in the Illinois State Industrial University, upon 
 certain measurements and tests made by him at our request to deter- 
 mine the relative fineness and strength of the fibre of samples of raw 
 silk raised at the Department. A noticeable result of these experi- 
 ments, as may be seen by reference to the accompanying tables, is 
 that the fibre from worms fed exclusively upon Osage orange is shown 
 to be somewhat finer, and, on the average, equal in strength to that 
 obtained from the mulberry -fed individuals. We also give a plate from 
 photographs taken by Dr. McMurtrie, illustrating the dual nature of 
 the fibre. 
 
 C. V. E. 
 
 * Dr. Bailey died July 1, 1883. 
 
OBSERVATIONS AND EXPERIMENTS 
 
 IN THE PRACTICAL WORK OF THE DIVISION 
 
 FURTHER NOTES ON THE ARMY WORM. 
 
 In the last annual report of the Department we published the most 
 important portion of the chapter on the Army Wosin in advance from 
 the Third Eeport of the United States Entomological Commission. In 
 this article we give some additional notes, together with an account of 
 the rather abnormal occurrence of the worms in the summer of 1882 in 
 certain cranberry bogs in Xew Jersey. 
 
 THE ARMY WORM IN 1883. 
 
 In spite of the fact that the spring of 1883 was favorable for the 
 development of the Army Worm, its scarcity almost all over the coun- 
 try has been remarkable. In few years within our recollection have 
 there been so few complaints of damage by the worm. In fact, no well 
 authenticated case of injury has come to our notice,* though in the lat- 
 ter part of Juue it was rumored to be present in force in Eastern 
 Pennsylvania. In the vicinity of Washington, in localities where last 
 year the moths were extremely numerous, but few individuals have been 
 found. 
 
 EXPERIMENTS UPON FOOD-PLANTS. 
 
 The normal food-plants of the Army Worm are found among the 
 grasses and grains, not a single species of either, so far as known, com- 
 ing amiss. Wheat and oats seem to be their favorite among the small 
 grains, though rye and barley are also taken with less relish. German 
 millet, corn, and sorghum are eateu by the worms, particularly when 
 young and tender. They were found in 1881 feeding to a greater or less 
 extent on flax in Illinois, although this is mentioned by Fitch as one of 
 the crops which the worms will not touch. They have also been re- 
 ported to eat onions, peas, beans, and other vegetables, though prob- 
 ably only when pressed with hunger. As stated in our Eighth Missouri 
 Eeport, upon the reliable authority of Mr. B. F. Mills, of Makanda, 111., 
 they have also been known to eat the leaves of fruit trees. Ordinarily 
 clover is disregarded by the worms, though they occasionally nibble at 
 it. A timothy field is often eaten to the ground, leaving the clover 
 scattered through it standing. In this connection it may be well to 
 
 * Since this was written it has been reported as injurious at East Windsor, Conu., 
 during June. 
 
 (9) 
 
% 
 
 10 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 state that on the Department grounds at Washington Ihe newly -hatched 
 worms have been found in a folded clover leaf, feeding thus protected, 
 and under such circumstances as rendered it probable that they had 
 been hatched there. 
 
 Mr. Lockwood stated in his report (see last Annual Report of this 
 Department) that even the common rag- weed (Ambrosia artemisicefolia) 
 was eaten clean by the worms, and also that the worms in passing 
 through a strawberry patch devoured both the leaves of the plant and 
 the unripe fruit. 
 
 In order to establish upon proper authority the facts concerning what 
 the Army Worm will and will not eat when pushed by hunger, we con- 
 ducted during the summer of 1881-'82 a series of experiments upon dif- 
 ferent plants, placing each plant in*a separate breeding-cage with a few 
 healthy half-grown larvae. The results show an unexpected power of 
 accommodation to plants in many families, and no resultant variation 
 in the imagines worth mentioning. 
 
 The results are summarized below : 
 P AP aver ace je. — Papaver somniferum. (Garden poppy.) 
 
 Of four larvae all attained full growth and entered the ground. Three 
 moths issued. 
 
 Crtjoieer^e. — Brassica oleracea. (Cabbage.) 
 
 The four larvae in this case moved restlessly about for the first day 
 without feeding. The second day they began to feed, and by, the fif- 
 teenth all had changed to pupa. In this state two died, but the other 
 two issued as moths. 
 
 Crucieer^e. — Baphanus sativus. (Raddish.) 
 
 Of four larvae two lived to issue as moths ; one died in the pupa, and 
 one in the larva state. 
 
 Malvaceae. — Gossypium Jierhaceum. . (Cotton.) 
 
 All died after feeding slightly. 
 Yitace^e. — Vitis labrusca. (Grape.) 
 
 All died without feeding. 
 LeGtUMInos^e — Piston sativum. (Garden pea.) 
 
 Of five larvae, all fed abundantly ; transformed and issued as inoths* 
 LegtUMINOS^e. — Phaseolus vulgaris. (Garden bean.) 
 
 All died without touching the leaves. 
 Rosacea. — Fragaria virginiensis. (Strawberry.) 
 
 The four larvae experimented on all fed for from seven to ten days 
 and then died without transforming. 
 
 Rosacea. — Bubus strigosus. (Raspberry.) 
 
 Of eight larvae, all fed well and all transformed to pupae ; only four, 
 however, issuing as moths. 
 
FOOD-PLANTS OF THE ARMY WORM. 11 
 
 Umbellifek.e. — Daucus carota. (Carrot.) 
 
 The four larvae begun feeding on the second day ; all transformed ; 
 two died in the pupa state and the other two issued as moths. 
 Oibelliferje. — Pastinaca sativa. (Parsnip.) 
 
 Of four larva?, one died before transforming, one in the pupa state, 
 aud the other two issued as moths. 
 CoiivosiTJE.—Lactuca sativa. (Garden lettuce.) 
 
 Of four larvae, one was destroyed by the others before they commenced 
 to eat ; the others all fed to full growth, transformed, and issued as 
 moths. 
 Chenopodiace^. — Beta vulgaris. ^Garden beet.) 
 
 Of four larv?e, after feeding slightly, three died after six days ; the 
 remaining one fed more extensively, transformed to pupa, and issued 
 as an apparently healthy moth. 
 Llliace^:. — Allium sativum. (Onion.) 
 
 All fed ; two died as larva?, and the other two completed the round 
 and issued as moths. 
 Conifer^e. — Abies canadensis. (Hemlock.) 
 
 All died without feeding. 
 
 THE ARMY WORM IN THE CRANBERRY" BOGS OF NEW JERSEY. 
 
 In June, 1882, there appeared on the Eockwood cranberry farm, near 
 Hammonton, N. J., an insect enemy which, according to the reports 
 received from Mr. Eockwood, first destroyed the rushes and afterwards 
 the young cranberry vines, thus doing considerable injury. Specimens 
 sent by Mr. Eockwood proved to be the larva? of a species of saw-fly, 
 which, however, in captivity refused to feed on the cranberry vines. 
 
 The following correspondence on this subject explains itself: 
 
 HammontoNj Atlantic County, New Jersey, 
 
 July 4, 1882. 
 To the Entomologist. Agricultural Department : 
 
 Sir : I send by this mail a box of worms which have done me great damage on a 
 cranberry bog. Some say that they are the Army Worm, but they did not come as 
 an army. They are on several cranberry bogs around, but no one has seen them trav- 
 eling. They are first found on the log, and are found of all sizes, from J inch long to 
 1| inches, and appear to have been hatched where they are found. The young have 
 only been seen on rushes in the ditches where water stands or was. The old spread 
 over the bog, eating first in preference grass, and then attacking the vines. They eat 
 the new, tender growth. The young are transparent and greenish, the full-grown 
 blackish. The large are active, moving rapidly. When touched they drop off the 
 vines and curl up. They work toward evening and apparently in the night. They 
 were first seen about June 20. We have killed some with Paris green, but they seem 
 to be disappearing, even where no Paris green has been used. We find dead bodies 
 where we have not used the poison ; but we still find the young and some old, although 
 not as many as a few days ago. Please tell me what you know about them. 
 Eespectfullv, 
 
 CHAS. G. ROCKWOOD. 
 
 P. S.— We have been unable to find a grown one at the time of day we got those I 
 send with this. They seem to touch nothing but grass and cranberry vines. 
 
12 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 Department of Agriculture, 
 
 Entomological Division, 
 
 July 6, 1882. 
 Mr. Chas. G. Rockwood, Newark, N. J. : 
 
 Dear Sir : Your favor of the 4th instant, with accompanying box, duly to hand. 
 The worms you send, and which are so destructive to your cranberries, are the larvre 
 •of a saw-fly (family Tenthredinidce ; order Hymenoptera) belonging apparently to the 
 genus Dolerus. I have found the same larva feeding on Juncus at Saint Louis, but 
 it has not before been reported to attack cranberry plants. The subject is therefore 
 of great interest to me, and you would greatly oblige me by sending on as many of 
 the worms as you are able to find, packed according to the above-printed directions. 
 I would also be thankful for any further observations you could furnish on the habits 
 and development of this pest. 
 
 Yours, truly, • 
 
 C. V. EILEY, 
 
 Entomologist. 
 
 Newark, N. J., July 7, 1882. 
 C. V. Riley, Esq., Entomologist, etc. : 
 
 Dear Sir : Your favor of the 6th received. I have written to my farmer to send 
 you more specimens. We thought when I was there that the worms had nearly done 
 their work; and at noon, when we tried to find them to send you, we could only find 
 the old ones. I had earlier in the day found one old one, before I thought of consult- 
 ing you. They had been on the land about two weeks, and at one time parts of the 
 bog were black with them. Worms supposed to be the same had been on a neighbor- 
 ing bog two or three years ago, and disappeared about July 1. . They have not been 
 seen there either year since, although the owner thought he found their eggs. The 
 same worms (so supposed) have been this year on farms 5 or 6 miles from us. They 
 are also on the cranberry bogs near by us. We are in the pine barrens. The cranberries 
 are surrounded with dikes or dams, so as to be completely covered with water in the 
 winter, from, say, December 1 to May 10, more or less, according to seasons and accord- 
 ing to the facilities of each location, each not having equal supply of water. We did 
 not get ours fairly flowed last year till near the end of December. I think the water 
 was off by May 10 or 12, having been let down gradually to addle the eggs of insects. 
 We found on July 4, in searching for full-grown insects, dead bodies all in shape, but 
 which when handled fell to pieces. I have told my farmer if he found others to send 
 them to yon. 
 
 The cranberry is an evergreen. The worms preferred grass and ate the grass grow- 
 ing among the vines first, and then took only the new this year's tender growth of the 
 vines and the buds for this year's fruit, leaving the vines just as they were before .the 
 season's growth began. The old growth was not touched. 
 
 On the reeds where we found the young worms we found no evidence of the young 
 worms eating the reeds. In one instance, near the worm, I noticed a little place 
 three-eighths inch long where the reed had been gnawed, and it may have been done 
 by the worm. ' 
 
 Respectfully, 
 
 CHAS. G. ROCKWOOD. 
 
 P. S.— As to the damage, about three-fourths of the buds for this year on my land 
 have been eaten, and three-fourths of the new growth for next year's bearing: My 
 crop will therefore be cut down three-fourths of the expected yield of 2,000 bushels. 
 
 The new growth has time yet to grow again and form buds for next year. That 
 you may judge of the importance of this matter, I will say that the loss may be esti- 
 mated in money at, say, $2,000. 
 
THE ARMY WORM IN CRANBERRY BOGS. 13 
 
 Department of Agriculture, 
 Entomological Division, 
 
 July 7, 1882. 
 Mr. Chas. G. Rockwood, Newark, N. J.: 
 
 Dear Sir: In regard to the saw-fly you sent me as injurious to cranberries, I will 
 say that in my breeding jars they refuse to eat the cranberry plants. It now occurs 
 to me that you may hare possibly overlooked the real authors of the mischief, and 
 that the saw-fly larva? have merely fallen upon the cranberry plants from some other 
 plant. I beg you now to ascertain whether the larvre really feed on the cranberries. 
 By doing so you will greatly oblige. 
 Yours, truly, 
 
 C. V. RILEY, 
 
 Entomologist. 
 
 Newark, N. J., July 10. 
 C. V. Riley, Esq., Entomologist : 
 
 Dear Sir : Your favor of the 7th instant has been received. There is no doubt that 
 the worm of which I sent you the young did the mischief by eating the vines. I sup- 
 pose that my farmer happened to put in the box only old cranberry vines. They do 
 not touch the old vines, but eat the young shoots off this year's tender growth, and 
 only after exhausting the supply of grass which grows among the vines. But eating 
 the new growth takes the fruit buds and destroys this year's crop, and takes also the 
 growth which is to bear next year. The worms undoubtedly feed upon the vines. They 
 leave upon the ground many leaves, but must consume largely. 
 
 When I was there, in spots not reached by the worms the new growth arose solid 
 above the old vines, say, 4 inches, so that nothing else could be seen. On the other 
 side of the ditch would be a patch eaten clean down to the old vines, leaving them as 
 they were when the water was taken off and before new growth has started, and the 
 whole patch 4 or 5 inches lower in solid growth than the ijntouched patch adjoining, 
 and of different color. 
 
 Respectfully, r 
 
 CHAS. G. ROCKWOOb. 
 
 We visited Mr. Rock wood, at Newark, X. J., shortly after the receipt 
 of his last letter, aud concluded from further information obtained that 
 the s&w-fly larvre were certainly not the authors of the mischief, but 
 that Jhe Army Worm in all probability did the damage. Yet, as doubt 
 remained, we were anxious to settle the question, and sent Mr. E. A. 
 Schwarz to make examination on the spot. The following is the report 
 of his observations : 4 
 
 jSir : In accordance with your directions I have made a study of the injury done to 
 Mr. Rockwood's cranberries as far as it was possible at the time, the insect that did 
 the damage having disappeared more than six weeks previous to my visit at Ham- 
 monton. 
 
 The Rockwood cranberry farm is divided into squares, each of about 50 acres, sur- 
 rounded by high dikes, anK intersected by numerous irrigation ditches. Two or three 
 other squares are just being constructed, but are not yet inclosed with dikes. The 
 cranberries being fully formed at the time of my visit, August 1, there was no diffi- 
 culty in taking in at a glance from the high dikes the extent of the damage done by 
 the insect. It was apparent that the damage was confined to a number of the smaller 
 squares formed by the irrigation ditches. On some of these hardly any berries were 
 to be seen, while other squares adjoining the damaged ones, and only separated from 
 these by the narrow ditch, were not injured at all. On the newly-constructed squares, 
 where there is an abundance of grass, the newly-planted vines had severely suffered. 
 
14 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 There is but little grass on the cranberry bogs under cultivation, and it was found 
 that those squares bad suffered most on which there was most grass, while on those 
 squares where the cranberry vines bad nearly exterminated the grasses very little or 
 no damage at all had been done. 
 
 No living srjeciinens of the insect that really did the damage could be found, as was 
 to be expected after the lapse of more than six weeks, the worms having been seen 
 on the bog about June 20; but the following traces thereof were discovered: 1. The 
 ground on the damaged squares was literally strewn with excrement, which, though 
 much decomposed at this time, was unmistakably that of a Lepidopterous larva; 2. 
 Numerous heads of a Noctuid larva were found on the ground, most of them in a badly 
 decomposed state, and but a few among them in fair condition. These heads were 
 so abundant that there could not be the least doubt that they belonged to the de- 
 structive larva. The Sarracenias growing in some places in the bog each contained 
 numerous specimens of the decomposed larvae, but in the course of the examination 
 a few fairly well preserved specimens were found ; 3. Of pupae, or rather empty shells, 
 very few could be found, and it appears that the wet ground had prevented the worms 
 from entering the same, and that they mostly perished above ground without trans- 
 forming ; 4. A number of empty Microgaster cocoons, indistinguishable from those of 
 M. congregatus. 
 
 I will also remark in this connection that I found two specimens, the only ones I 
 saw, of the saw-fly sent by Mr. Van Hise as the originator of the damage. It was 
 feeding on a species of Scirpus (?) which grows in the irrigation ditches.' 
 
 The cultivated bog is flooded with water during winter and spring to a depth of 
 several feet, so that no Lepidopterous larvae can hibernate in it. The uncultivated 
 part is also under water most of the time mentioned, but not so thoroughly as the 
 cultivated portion. Outside of the cranberry lands there is but little graminaceous 
 • vegetation in the pine barrens. On the 10th of May the water is drawn off from the 
 bog, an operation which is accomplished in little more than 24 hoars. After this 
 the cranberry vines and other vegetation start vigorously, the grasses, one or two 
 species of which grow in thick bunches, being there much fresher than anywhere else 
 in the neighborhood. 
 
 From Mr. Eockwood's and Mr. Van Hise's observations there can be no doubt that 
 the larvae first devoured every blade of grass on the squares where the eggs were de- 
 posited and that they afterwards, from mere want of other food, began to attack the 
 cranberry vine^. They destroyed only the young vines (i. e., those which should have 
 been bearing this and the next seasons), eating the young, fresh leaves before these 
 had fairly opened. At the time of my visit these young twigs had the appearance of 
 being cut with a knife. Mr. Van Hise further states that he saw the worms appear 
 in great numbers at the edge of the irrigating ditches, a great many of them being in 
 the water and on the rushes growing in the ditches. This observation is no doubt 
 correct, as the worms, after passing through one of the squares, finally congregated 
 at the edge of the irrigating ditch and tried to get across, and in doing so got at the 
 rushes, which at the time of my visit still bore evidence of their attack. In general 
 the irrigation ditches were evidently an effectual barrier against the progress of the 
 worms, and whether they succeeded, in one or two instances, in crossing the ditches, 
 or whether the damage on the adjoining squares was caused by worms that hatched on 
 the same, could not be ascertained. At any rate their feeding on the rushes in the 
 water was the reason of the confusion in regard to the saw-fly larvae. Mr. Van Hise, 
 being instructed to collect specimens of the cranberry enemy at a time when the real 
 depredators had disappeared, naturally did not find any other worms on the rushes 
 than the saw-fly larvae, which seem to have been very numerous in the beginning of 
 July. 
 
 In regard to other injurious insects observed by me on the cranberry bogs, I would 
 mention that at the time of my visit serious damage was done by various species of 
 locusts (Acrididce), by eating large holes in the berries. Mr. Van Hise resorts to the 
 
THE ARMY WORM IN CRANBERRY BOGS 15 
 
 following remedy against this x>est: In company with another person he drags along 
 rope across the hog, thus driving away many of the locusts, or at least disturbing 
 them. He says that if this operation were repeated about twice each day the damage 
 would be considerably reduced, as the disturbed locusts do not settle down again to 
 their destructive work until after the lapse of several hours. 
 
 No " berry moth" could be observed on Mr. Rockwood's cranberry farm, but con- 
 siderable damage had been done earlier in the season by another Tortricid larva, 
 which webs together the terminal leaves of the young vines. At the time, of my visit 
 not a single living specimen could be found, but I believe that an additional flooding 
 of the bogs would prove a good remedy for this pest. 
 
 Respectfullv. 
 
 E. A. SCHWARZ, 
 
 Assistant. 
 Prof. C. V. Riley. 
 
 V. ' S. En tomologist. 
 
 A careful examination of the more or less irrecognizable specimens 
 found by Mr. Schwarz left little doubt in our minds that the species 
 was the genuine Army Worm, a few of the heads making this decision 
 possible. 
 
 It is evident from the facts observed by Mr. Schwarz that the moth 
 had flowu from some distance, for the records for that year, as indicated 
 in our last report, show that the insect was quite prevalent throughout 
 that portion of the United States at the time. • 
 
 Remedies. — It follows from the facts obtained that one of the best 
 ways of preventing injury to cranberries in the future is to keep the bog 
 as free as possible from foreign plants, and that the injury may be limited 
 by increasing the number of irrigating ditches and by keeping these free 
 from weeds and other obstructions. 
 
 Another method to prevent the recurrence of such invasion of .the 
 Army Worm suggest itself: The water is drawn off from the bog- 
 on May 10, and the plants not Hooded again for the rest of the season. 
 The irrigating ditches are then only kept filled with water in given quan- 
 tities, according to the character of the season. Fow, the water can be 
 drawn off earlier than has hitherto been done, without injury .to the 
 plants, and, what is more important in this connection, the water can 
 be let on again without injury to the plants at any time before bloom- 
 ing, i. e., about the last week of June, vlf the eggs are laid by the moths, 
 as was evidently the case in 1882, during the month of May, it is ap- 
 parent that a flooding of the bog some time during the month of June 
 (the water to be kept on the bog, say, for about two days) would drown t 
 out the worms before they have begun to do the damage. 
 
 Wherever an abundant water supply is at command in spring and 
 early summer, and under control, as is the case on the cranberry farms 
 near Hammonton, a repetition of the damage done by the Army Worm 
 could thus easily be avoided. Should the worm appear during or after 
 the blooming season little or nothing could be done against it; but it is 
 probable that at this time the damage done by the worms would be much 
 less serious than earlier in the season, as the leaves on the bearing vines 
 will then be too hard to be verv attractive. 
 
16 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 EXPERIMENTS WITH PYRETHRUM. 
 
 We treated so fully of this insecticide in our annual report for 1881-2 
 that the value of the powder and the modes of using it are now pretty 
 well understood. The following account of experiments made by Mr. 
 Howard will, however, prove interesting, as we had them instituted in 
 order to show how the different larvaB experimented with were severally 
 affected by it. 
 
 1. SPECIAL EXPERIMENT WITH CUTLERS' POWDER NO. 1. 
 
 September 20, 11.45 -a. m. — Three healthy, half-grown larvae of the 
 Fall Web-worm (Hypliantria textor) placed in small glass tumbler, and 
 a very small quantity of Cutlers 7 ~No. 1 puffed on the anterior abdomi- 
 nal segments of each ; tumbler covered with glass slip. 
 
 In four minutes one seemed affected ; moved the head quickly from 
 one side to the other, arched the back, and made rapid jumping move- 
 ments as if trying to get rid of the powder. In b* minutes all were sim- 
 ilarly affected. At 7 minutes the one first mentioned was struggling 
 violently and incessantly, jumping and writhing the whole body, now on 
 its back and again on its side ; no intervals of rest except momentary 
 in this extremely ft/pid motion. 
 
 In ten minutes became quieter, but was still bending the body in all 
 directions ; incessantly writhing like a mammal poisoned with strych- 
 nine. 
 
 12.2. — Motions have become more spasmodic and jerky, and have lost 
 to certain degree the smoothly writhing character. 
 
 12.10. — Motions much slower and consist of a slow writhing of the 
 whole body. 
 
 12.18. — Motion still slower ; the true legs trembling violently at in- 
 tervals. 
 
 12.28. — The motion of the body has become very slow, but the legs 
 are constantly twitching. The rectum is somewhat everted and the ab- 
 dominal segments have become somewhat contracted. 
 
 12.50. — The body is still more contracted, though still moving slightly, 
 the legs still trembling somewhat. 
 
 1.40. — The abdomen is still more contracted, but a slight motion is 
 left, which shows that the final paralysis is that of exhaustion rather 
 than of tetanus. 
 
 2.00. — Apparently almost dead ; only a slight occasional motion of 
 prolegs and mouth parts, with an occasional twitch of one of the true 
 legs. 
 
 3.20. — A very slight motion still perceptible ; the bodies have 
 shrunken to very small proportions. 
 
 September 21, 9 a. m.— Still a slight motion of legs and mouth parts, 
 and one moves also one of its prolegs. 
 
 1.15 p. m. — No change. 
 
EXPERIMENTS WITH PYRETHRUM. 17 
 
 3.00.— Still no change. 
 
 September 22, 9.30 a. m. — No motioii left except a very slight occa- 
 sional twitching of the anterior prolegs. 
 
 2. PARALLEL EXPERIMENT IN OPEN AIR. 
 
 September 20, 11.45 a. m. — A larva similar in all respects to the pre- 
 ceding was dusted in the same manner with the same powder, in the 
 same quantity, at the same time. 
 
 In 10 minutes it began to show signs of uneasiness. In 13 minutes 
 began to struggle. The spasms increased in violence until 12.50 when 
 they began to subside. There were still strong writhings at 3.30, and 
 the body had only just begun to contract ■; while the confined worms 
 had reached a similar condition at 12.30. 
 
 At 9 a. in., September 21, the body had shrunken enormously, but 
 there was still motion of the entire body. 
 
 3.30 p. m. — No perceptible change. 
 
 September 22, 9.30 a. m. — Dead. This seems strange in view of the 
 fact that the confined larvae which were strongly influenced by the pow- 
 der at a much earlier period are still alive. 
 
 EXPERIMENTS 3 AND 4. 
 
 The following experiments were made with nine samples of powder : 
 1st, the ordinary powder sold by Cutler Bros. & Co., of Boston, next, 
 five samples labeled Cutler Bros. No. 1, No. 2, No. 3. No. 4, and No. 5, 
 sent to the Department for comparative test; 7th, pyrethrum imported 
 by Lehn & Fink, of New York City, in- 1881 ; 8th, the 1882 importation 
 of the same firm ; and 3 9th, a powder made from flowers raised by Pro- 
 fessor Eiley in 1882. 
 
 In experiment 3, six young larvae of Hyphantria textor, about one- 
 fourth grown, were placed in each of nine labeled, closed tin boxes 
 (11x8.5x3.5 cm.), and a small quantity of each sample of powder was 
 dusted on the dorsum of the anterior abdominal segments of the worms 
 in each box. 
 
 In experiment 4, three half-grown larvae of the same insect were used 
 in the same boxes and dusted in the same manner. Each worm received, 
 as nearly as could be judged by the eye, the same quantity of the pow- 
 der. 
 
 5135 2 
 
18 
 
 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 
 
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EXPERIMENTS WITH PYRETHRUM. 
 
 19 
 
 All in violent 
 convulsions. 
 
 All fi n i sli ed 
 the violent 
 stage. 
 
 All consider- 
 ably feebler. 
 
 All shrunken 
 and feeble, 
 but not so 
 much so as 
 
 preceding. 
 
 One very feeble; 
 two dead. 
 
 No change. 
 No change- 
 All dead. 
 
 Convuls i o ii s 
 not yet be- 
 gun. ' 
 
 All finished 
 the violenl 
 
 stage. 
 
 One appears to 
 
 be recover- 
 i n g ; t w o 
 quieter. 
 
 One almost re- 
 covered ap- 
 parent 1 y ; 
 two shrunk- 
 en and very 
 sick. 
 
 One very sick; 
 one a lm os t 
 gone; one 
 dead. 
 
 One almost 
 g o D e ; one 
 more dead. 
 
 One still alive. 
 AH dead .... 
 
 Convulsions 
 begi ii n i n g ; 
 quite strong. 
 
 One still nor- 
 mal ; # one still 
 viohnit; one 
 passed the 
 violent stage. 
 
 No change 
 
 One normal ; 
 two shrunk- 
 en, but still 
 strong. 
 
 One still nor- 
 m a 1; two 
 dead. 
 
 The last one 
 taken w i t li 
 convulsions. 
 
 Si ill strug- 
 gling. 
 
 Still a 1 i v e, 
 though feeble. 
 
 Slightly con- 
 vulsed. 
 
 All finished 
 the viol en t 
 stage. 
 
 Feebler, tho' 
 not markedly 
 so. 
 
 All much 
 feebler a n d 
 
 shrunken. 
 
 All t h ree 
 dead. 
 
 
 
 Two in violent 
 convulsions ; 
 one not yet 
 
 seized. 
 < )nc apparent- 
 ly n or in a 1 ; 
 two still vio- 
 lent. 
 
 No change 
 
 One nonnal ; 
 two quieter 
 and b e gin- 
 ning to con- 
 tract. 
 
 One just alive; 
 two dead. 
 
 All dead 
 
 
 
 Not yet con- 
 vulsed, 
 
 All just linished 
 violent stage. 
 
 No marked 
 c h a n g e ; 
 quieter. 
 
 N o m a r k e d 
 C h a n g e ; all 
 s o m e w h at 
 shrunken. 
 
 One strong, re- 
 covering; one 
 shrunken and 
 feeble; one al- 
 most dead. 
 
 One recovering; 
 one very fee- 
 ble ; one almost 
 dead. 
 
 gone; two 
 dead. 
 
 AH dead 
 
 All in violent 
 
 convulsions. 
 
 All apparently 
 
 j u st p a 88e d 
 through vio- 
 lent stage. 
 
 All quiet ; one 
 worse than 
 others. 
 
 No marked 
 C h an g e ; all 
 much shrunk- 
 en. 
 
 All alive, though 
 
 feeble. 
 
 One just alive ; 
 two dead. 
 
 
 
 All in violent 
 convulsions. 
 
 Two have passed 
 
 through the 
 s p as m o d i o 
 stage ; o n e 
 still struggling 
 violently. 
 
 One normal; two 
 more quiet and 
 beginning t o 
 contract. 
 
 The normal one 
 t a ken wit h 
 8 p a s in s; two 
 in o re co n- 
 tracted an d 
 feebler. 
 
 One just alive ; 
 
 two dead. 
 
 No change 
 
 No chanere 
 
 1 
 
 5 
 
 
 All in violent 
 convulsions. 
 
 Two have be- 
 come quiet and 
 are badly af- 
 fected; one 
 crawls rapid- 
 ly, without 
 spasms. 
 
 One normal; 
 two more quiet 
 and beginning 
 to contract. 
 
 One normal; 
 one appears as 
 if recovering ; 
 one feeble, but 
 still alive. 
 
 One normal; one 
 slightly mov- 
 ing; o n e 
 dead. 
 
 No change 
 
 No change 
 
 One lively, but 
 starved, not af- 
 fected; one 
 more dead. 
 
 September 20. 
 
 (Placed in box at 
 
 11.16 a. m.) 
 11.30 a. m '- 
 
 12.20 p. in 
 
 1.25 p. m 
 
 a 9n n 
 
 Septkmhku 21. 
 !) a. m 
 
 1.05 p. m 
 
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 K 
 
 CO 
 
 ci 
 
 s a 
 
 r- 
 
 d a 
 
 
20 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY 
 
 EXPERIMENT NO. 5. 
 
 September 22. — Twelve larvae of Plusia brassicce and four of Pionea 
 rimosalis were placed in one of the tin boxes and sprinkled in the usual 
 manner with Cutlers' No. 5, the powder which had given the best re- 
 sult in the last experiment. 
 
 In 5 minutes the Pionea larvae were affected, and in 10 minutes the 
 small Plusias ; the full-grown Plusias not until 25 minutes. The effects 
 upon all were very marked. The rectum was everted, and large quanti- 
 ties of a greenish liquid were ejected from the mouths of the Plusias. 
 
 At 35 minutes two of the largest Plusias still appeared normal. The 
 skin of the Plusias being so delicate the heart beat was watched without 
 much difficulty. In the normal individuals the pulse was found to 
 range, after numerous trials, from 44 per minute to 68, averaging about 
 56. 
 
 The pulse of one of the large worms in its first spasms marked 164, 
 and 8 minutes later it had fallen to 150, and in 15 minutes later still to 
 140. 
 
 In a smaller one, which had passed through the first convulsions and 
 had become feeble, the pulse was almost imperceptible from weakness, 
 and though still very fast (136 per minute) had evidently fallen. 
 
 At the expiration of 18 hours the Pioneas were all dead, and 4 of the 
 smaller Plusias were also dead. Two of the Plusias had spun up and 
 the remaining 6 appeared perfectly healthy and normal. The pulse of 
 these last varied from 44 to 64. 
 
 September 24. — Three more of the larvae spun up, and the first two 
 transformed to healthy pupae. 
 
 September 25. — The three larvae which spun up on the 24th have trans 
 formed to healthy pupae. 
 
 September 27. — The remaining larva which recovered from the dosing 
 is still strong and active. 
 
 September 28. — This larva has also spun up and transformed to a 
 healthy pupa. 
 
 EXPERIMENT NO. 6. — EXPERIMENT WITH CUTLERS' " SPECIAL INSECT 
 POWDER FOR ROACHES AND WATERBUGS." 
 
 The base of this powder is Dalmatian pyrethrum, but from the odor 
 it apparently contains some red pepper. 
 
 September 22. — A full-grown larva of Hyphantria textor was placed in 
 a closed glass jar and thickly dusted with this powder, which stuck to 
 the hairs in masses. It was seized with no convulsions, and September 
 27, after 120 hours, is still alive, though much shrunken and feeble from 
 starvation. The powder apparently had no effect upon it. 
 
 September 22. — Four full-grown cockroaches were placed under an in- 
 verted tumbler, and a small quantity of this powder puffed in from an 
 insufflator. In 15 minutes all were taken with spasms, and in an hour 
 
EXPERIMENTS WITH PYRETHRUM. 2 1 
 
 were lying helpless upon the table, although still retaining considerable 
 vitality. In twenty hours they were dead. 
 
 EXPERIMENT NO. 7. — EXPERIMENT UPON LARVAE OF DAT ANA MIN- 
 ISTER. 
 
 This experiment was conducted in the same manner as Experiment 
 No. 4. Three full-grown larvae of Datana ministra were placed in each 
 of nine tin boxes and sprinkled in the same manner with the same 
 amount of the different poisons. The boxes this time, instead of being- 
 covered with their own tight tin covers, were covered with slabs of glass, 
 which, on account of the irregularities in the edges of the boxes, did not 
 fit tightly, and allowed for a pretty free circulation of air. But this per- 
 haps was compensated for by the fact that the covers did not have to be 
 lifted to observe the condition of the larva?. The fact should be remem- 
 bered in comparing this experiment with Xo. 4. The following table 
 shows the result, and it will be noticed that the Datana is susceptible 
 in a remarkable degree to the action of the pyretbrum when compared 
 with Hyphantria or Plusia : 
 
22 
 
 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 
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EXPERIMENTS WITH PYRETHRUM. 23 
 
 EXPERIMENT NO. 8. 
 
 September 28, 10.50 a. m. — Seventeen full-grown larvfe of Datana 
 ministra placed in a large breeding-cage open at top, and a small quan- 
 tity of Cutlers' Xo. 5 blown in through an insufflator, making an at- 
 mosphere of dust. 
 
 11 a. m. — Some half dozen are writhing uneasily. 
 
 3 p. m. — Four are in convulsions. 
 
 September 29, 10 a. in. — Two are practically dead, only a slight motion 
 of the thoracic legs remaining ; two more on their backs, and only mov- 
 ing slightly. The rest are evidently somewhat affected, but retain their 
 normal position, and are capable of strong motion. 
 
 3.30 p. m. — One dead; live others badly affected. 
 
 September 30, 9 a. m. — X change. 
 
 Oetober 1, 9 a. m. — Five more dead. 
 
 October 2, 9 a. m. — Six more dead. The others appear perfectly nor- 
 mal. 
 
 Xote. — This experiment possesses much interest when compared with 
 experiment 7, as indicating the effects of the powder in a tightly-closed 
 box and in an open cage, the latter approaching open-air conditions. 
 • 
 
 EXPERIMENT NO. 9. 
 
 September 29, 2.30 p. m. — A limb of hawthorn in the open air crowded 
 with the Hawthorn Schizoneura {Scliizoneura lanigera ?) puffed upon 
 copiously with Cutlers' Xo. o, so that every individual must have had a 
 dose. 
 
 October 1, 9.30 a. m. — Could see no effect whatever. The lice were 
 just as numerous and just as healthy. 
 
NOTES ON FOREST-TREE INSECTS. 
 
 By A. S. Packard, Jr., M. D., Special agent of the Division. 
 
 AFFECTING THE CEDAR OR ARBOR VIT^E. 
 
 EUP1THECIA MISEBULATA Grote. 
 
 Although the moth is very common, occurring all over the Eastern 
 United States, flying about and entering our houses through the sum- 
 mer, the caterpillar is rarely met with, though it is liable to prove lo- 
 cally injurious to cedar hedges and ornamental trees. We have reared 
 the moth from caterpillars found on the low bush juniper (Juniperus 
 communis), and descriptions of the larva and chrysalis will be found in 
 Bulletin 7 of the U. S. Entomological Commission, p. 248. The follow- 
 ing descriptions were drawn up from a specimen living during the last 
 week of August, the chrysalis appearing September 30 on the cedar in 
 Maine, the moth appearing the following spring, early in May, in con- 
 finement: 
 
 Larva. — Body slender, the sutures between the segments well marked and stained 
 with yellow. The head small, rounded, not bilobed, and not so wide as the body # 
 Uniformly pale green, exactly concoloroits with the leaves of the cedar, on which it 
 feeds. The lateral fleshy ridge of the body is marked with greenish-yellow, forming 
 a prominent, interrupted, greenish-yellow lateral line. Supra- anal plate very short? 
 smooth, obtuse at the apex, the edges marked with greenish-yellow. Anal legs thick 
 and short, not broad; no dorsal warts or tubercles, the body being smooth. Length 
 
 Pupa. — Green, slender. Length 7-8 mm . 
 
 AFFECTING THE FIR, SPRUCE, AND HEMLOCK. 
 
 EUPITHEOIA LUTEATA Pack. 
 
 This is a common caterpillar on evergreen trees, excepting the pine, 
 and is described in Bulletin 7, IT. S. Entomological Commission, p. 237. 
 The caterpillar is rather flat, the surface granulated, the body reddish 
 and bearing a remarkable resemblance to a red, dead fir leaf. It turns 
 to a chrysalis late in August and early in September in Maine, and the 
 moth appears the following May and June. 
 
 The moth differs from Eupithecia miserulata in the much longer, more 
 pointed fore wings. The palpi are also larger, acute, and black. It 
 has four regularly-curved, parallel black lines on both wings ; it is also 
 characterized by the broad, clear, flesh-yellow or luteous band situated 
 between the discal dot and the extra-discal line. Expanse of wings 
 22 mm . 
 
 (24) 
 
NOTES ON FOKEST-TREE INSECTS. 25 
 
 AFFECTING THE PINE. 
 
 THE PIXE CARIPETA. 
 
 (Caripeta angustioraria Walk.) 
 
 This is frequently met upon the white pine (Pinus strobus) in August 
 and September throughout the Xew England States, and as late as the 
 first week in October in Rhode Island. Specimens become full-fed by 
 the 8th of August in Maine, and before entering the chrysalis state spin 
 a whitish web, with minute meshes, not a loose web. On the day follow- 
 ing the chrysalis appears, and the moth appears in May and June of the 
 following year. It is one of our most showy geometrid moths. 
 
 The larva. — Body rather large and thick, thickest on the segment hearing the first 
 pair of ahdominal legs. Head nearly as -wide as the prothoracic segment, very 
 slightly angulated on each side of the vertex, mottled with dusky spots or marhled 
 with transverse, parallel waved lines. The prothoracic segment rather small, not an- 
 gulated in front, provided ahove with small warts. On each ahdominal segment a 
 high, transverse, prominent, smooth ridge, somewhat saddle shaped and hearing at 
 each end a piliferous wart. On the third and second segments from the end no such 
 ridge, these heing replaced hy piliferous warts, the two on the penultimate segment 
 heing rather high and situated near together. Behind these two tubercles on a trans- 
 verse wrinkle are two small dark warts, and on a succeeding wrinkle are six warts. 
 On the supra-anal plate are four warts, and on the end, which is ohtuse, are four small 
 hair-hearing warts. There are similar hairs on the edge of the anal legs, which have 
 a deep crease parallel to the front edge ; the lateral ridge is large and rough and inter- 
 rupted at the segments. The hody elsewhere is variously tuherculated, with hairs 
 arising from the warts. The body in general is pale whitish-gray, with a lilac tint or 
 slate color, variously marhled with dark-brown and sometimes with a decided reddish 
 tint. Length 32 ram . 
 
 Pupa. — Rather stout. Brown, with an obscure dorsal row of irregular spots form- 
 ing a nearly continuous line or band ; a lateral row of large, obscure spots; second 
 abdominal segment from the encl of the legs with two warts beneath. Length 15 mm . 
 
 The moth. — It differs remarkably from any other species of the family by the rich, 
 opake, velvety, ochreous fore wings, with the three broad silvery lines and large dis- 
 cal dot. The head, antenna?, and thorax are pale ochreous. Fore wings opake, deep 
 ochreous, paler at the base ; on the inner fourth is a white line forming a single large 
 and acute angle on the median vein, along which it is prolonged beyond the basal 
 third of the wing, extending out nearly as far as the distal dot, though situated be- 
 low it. There is a large, irregular, silvery- white discal dot and just beyond a 
 broad silvery line, diffuse on the outside; it curves inward just below the median 
 vein and slightly inward opposite the discal dot. Half-way between this line and the 
 outer edge of the wing is a row of irregular white spots, from which sometimes run 
 whitish streaks to the fringe, which between the white spots is ochreous-brown. 
 The hind wings are pale whitish-ochreous above ; beneath, washed with yellow-ochre- 
 ous upon and on each side of the venules. Expanse of wings 3G mm (1.60 inches). 
 
 AFFECTING THE OAK. 
 
 THE OAK-LEAF CRYPTOLECHIA. 
 
 (Cryptolechia scldagenella Zeller.) 
 
 This is a remarkable insect, both as a caterpillar and moth. It is not 
 uncommon in the larval state on the oak, where we have seen it in Maine 
 
26 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 and Ehode Island in September. It feeds between the leaves, drawing 
 them together with silk threads. When abont to pupate it turns over 
 a portion of the leaf nearly an inch long, lines the interior of the cell 
 thus made with silk, and the moth appears the following spring. We 
 have compared the moth with a type specimen sent to us by the late 
 Prof. P. 0. Zeller several years ago, and now in the museum of the Pea- 
 body Academy of Science, Salem, Mass., and it is undoubtedly that 
 species, though the row of blackish dots so distinct in the fresh speci- 
 men reared by us is not to be seen in the type specimen ; otherwise it 
 agrees exactly with the latter. It is not an uncommon insect, but, so far 
 as known, more curious than destructive, though it may at times disfig- 
 ure the leaves of valuable shade trees. 
 
 The larva. — Head large, broad, and flat — as broad as the protlioracic segment ; pale 
 horn or whitish color, surface rough ; in front crossed by two dark reddish-brown broad 
 lines which form two large shallow scallops; the front line extends along the sides, 
 including the eyes and the front edge of the clypeus ; the other is broader, forming two 
 scallops and crossing the apex of the clypeus. On each side of the head below the 
 front line is a short, nearly straight, brown-black line not reaching as far as the eyes. 
 The median suture of the head is rather deeply impressed ; the vertex on each side is 
 a little swollen and marked with eight or nine dark reddish-brown more or less con- 
 fluent spots. The posterior edge of the head is edged with black-brown. The body 
 is somewhat flattened, pale pea-green, a little paler than the under side of the leaf. 
 Prothoracic segment without a shield, but broad, flat, and green like the rest of the 
 body. On the sides of the three thoracic segments is a dark tubercle tinged with 
 reddish between, forming a lateral thoracic line. No dorsal tubercles, but pale hairs, 
 as long as the body, arise from minute points, which are obscurely indicated. 
 Length, 23 mm . 
 
 The pupa. — Body very thick and stout; the head broad, and the abdomen short and 
 thick; the end of the body very blunt, the tip broad and obtuse, somewhat tubercu- 
 lated, not spined. The wings reach to the end of the fifth abdominal segment, and 
 on the under side of the sixth and seventh segments are two dark, ventral, small cal- 
 losities ; the tip is broad, truncated, rough, and dark. Length 10 mm ; thickness 3.5 mm . 
 
 The moth. — A very large species for the family to which it belongs. Head with the 
 scales between the antenna?, and on the vertex loose and thick, not smooth as in Ge- 
 lechia. Palpi long and slender, smooth, the third joint very long and slender, over 
 one-half as long as the second. It is so large and the fore wings so broad and oblong, 
 that at first it might be mistaken for a Tortrix. 
 
 Body and wings snow-white. Fore wings snow-white with two smoky, twin dots 
 at the base of the wing near the costa; two smoky spots inside of the middle of the 
 wing on the internal edge. Beyond the middle of the wing are five or six indistinct, , 
 pearly, smoky spots, the central one apparently forming the discal dot. Two faint, 
 curved, smoky lines parallel with each other and with the outer edge, neither of them 
 reaching the costal edge of the wing, and the inner less than one-half as wide as the 
 outer. On the outer edge of the wing, on the white fringe, is a row of about five con- 
 spicuous dark brown spots; the base of the fringe is smoky, forming a faint line. 
 Body, hind wings, abdomen, and legs snow-white; antenna? light brown. On hinder 
 part of the thorax, very distinct when the wings are closed, is a large prominent tuft 
 of broad brown scales, which send off different metallic colors, especially steel-blue. 
 Length of body 9-10 mm ; of fore wing 11mm • expanse of wings 24 mm . 
 
THE SPRUCE BUD- WORM IN MAINE. 27 
 
 FURTHER FACTS REGARDING THE EXTENT OF THE RAVAGES OF THE 
 SPRUCE BUD- WORM IX MAINE. 
 
 The following facts regarding the extent of the ravages of this cater- 
 pillar on the coast of Maine were gathered daring the summer of 1883, 
 and for want of space omitted from the report published in that of the 
 Entomologist of the Department of Agriculture. 
 
 The westernmost locality at which the spruce bud-worm was observed 
 was on Peak's and other islands in Portland Harbor, the spruce not 
 extending in any great quantity west of that city. The spruces about 
 Sebago Lake were also destroyed by this worm- or a similar caterpillar, 
 in 1878, as we are informed by Rev. Mr. Kellogg, a Mr. Townseud be- 
 ing his authority. Around the shores of Casco Bay and on many of 
 the islands, especially Birch Island, Orr's Island, Jewell's Island, and 
 Great or Harpswell Island, also on Harpswell Neck, Mere Point, Prince's 
 Point, as well as other peninsulas extending into Casco Bay, Wherever 
 the spruces and firs grow thickly, extensive areas of these trees were 
 observed; also similar masses of dead spruce were observed along the 
 Maine Central Railroad, from Portland to Brunswick, and thence to 
 Bath; also on the shores of Cathauce River, at and near Bowdoinham, 
 Me. Wherever the fiords or narrow bays and reaches extend inland, 
 in Cumberland and Sagadahock, as well as Lincoln Counties, the spruce 
 and fir forests clothing their shores had been invaded by this destruc- 
 tive caterpillar. Wherever the spruces were abundant on the Kenne- 
 bec River, below Bath, particularly on the eastern side, at aud near 
 Parker's Point, and also at and west of Fort Popham, there were ex- 
 tensive patches of dead spruces. Similar but smaller masses of dead 
 spruce were observed along the steamer route from Bath to Boothbay 
 Harbor, at and to the eastward of Southport; none were observed on 
 Mouse or Squirrel Islands. In the course of a journey, at the end of 
 July, from Brunswick along the coast to Eastport, we were able to ascer- 
 tain the eastern limits of the ravages of this worm. Several clumps of 
 spruces which had just died were seen on the Knox and Lincoln Railroad 
 before reaching the Wiscasset Station. At Waldoboro', southeast from 
 the station, was an extensive area of dead spruces which presented the 
 same characteristic appearance as in Cumberland County, and for two 
 or three miles beyond Waldoboro' there were to be seen large masses of 
 dead spruces and firs. Beyond Warren no dead spruces were to be seen ; 
 none were observed about Rockland, Camden, Blue Hill, or the islands 
 of Penobscot Bay ; none on Mount Desert, or the islands from Mount 
 Desert to East Machias, nor on the road from East Machias to Lubec, 
 although the predominant growth is spruce. No dead spruces were to 
 be seen about Eastport, nor along the Saint Croix River, to Calais, and 
 none along the railroad from Saint Stephens to Vauceboro' aud thence 
 to Bangor. From. personal observation and inquiry it is safe for us to 
 report that east of the Penobscot River, in eastern Maine, south of 
 Aroostook County, there are no areas of dead spruce. Returning to 
 
28 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 Brunswick from Bangor, the characteristic patches or large clumps of 
 dead spruce and fir were not seen until we reached a point south of 
 Richmond, and near Bowdoinham, on and near tide water on the Cat- 
 hance River. The general absence of any extensive areas of dead spruces 
 around the Rangeley Lakes and the White Mountains has already been 
 referred to in our report. It thus appears that the injury from this worm 
 has been confined, at least south of Aroostook County, to an area on 
 the coast extending from Portland to Warren, and extending but a few 
 miles inland from the sea or tide- water. 
 
 The injury resulting from the attacks of the bud-caterpillar are char- 
 acteristic, as we have stated, the trees dying in masses or clumps of 
 greater or less extent, as if the moths had spread out from different cen- 
 ters before laying their eggs and the caterpillars, hatching, had eaten the 
 buds and leaves, and caused the trees to locally perish. From all we 
 have learned the past season we are now convinced that the spruce bud- 
 worm (Tortrix fumiferana) is the primary cause of the disease on the 
 coast. As remarked to us by the Rev. Elijah Kellogg, of Harpswell, Me., 
 who has observed the habits of these caterpillars more closely than any 
 one else we have met; where the worms have once devoured the buds the 
 tree is doomed. This, as Mr. Kellogg remarked, is due to the fact that 
 there are in the spruce but a few buds, usually two or three at the end 
 of a twig; if the caterpillar destroys these the tree does not reproduce 
 them until the year following. If any one will examine the buds of the 
 spruce and fir they will see that this must be the case. Hence the ease 
 with which the attacks of this caterpillar, when sufficiently abundant, 
 destroy the tree. We have not noticed that the spruce and fir throw 
 out new buds in July and August after such an invasion, the worm dis- 
 appearing in June. On the other hand, the hackmatack or larch when 
 wholly or partly defoliated by the saw-fly worm ( Nematus) soon sends 
 out new leaves. By the end of August we have observed such leaves 
 about a quarter of an inch long. In the following spring a larch which 
 has been stripped of its leaves the summer previous will leave out again 
 freely, although the leaves are always considerably, sometimes one-half? 
 shorter. Now, if any one will examine the leaf buds of the larch it will 
 be seen that they are far more numerous than in the spruce and fir or 
 other species of the genus Abies, being scattered along the twig at inter- 
 vals of from a line to half an inch apart. Hence the superior vitality of 
 the larch, at least as regards its power of overcoming or recuperating 
 from the effects of the loss of its leaves in midsummer. Besides this, 
 the bud- worm of the spruce and fir is most active and destructive in June, 
 at the time the tree is putting forth its buds, while the hackmatack, 
 which drops its leaves in the autumn, has become wholly leaved out 
 some weeks before the saw-fly worms appear. For these reasons, while 
 the spruce and fir usually die if most of the leaves and buds are eaten 
 after the first season's attack, the larch may usually survive the loss of 
 leaves for two seasons in succession. 
 
THE HACKMATACK OR LARCH SAW-FLY. 29 
 
 Id addition to the facts regarding the great abundance of the bud- 
 worm we may cite information given us by Prof. L. A. Lee, of Bowdoin 
 College, who observed the bud-worms in June, 1880, upon the spruces 
 at Prince's Point, Brunswick, and had no doubt but that they were suf- 
 ficient to cause the death en masse of these trees. In 1883 we visited the 
 locality, and many of the trees had been cut down for fuel. 
 
 From Rev. Mr. Kellogg we learned the following interesting facts re- 
 garding the appearance of a similar, most probably the same, species of 
 caterpillar, even upon the same farm that was ravaged in 1878, early 
 in this century. According to Capt. James Siunett and Mr. John Jor- 
 dan, of Harpswell, the spruces of Harpswell and Orr's Islands were de- 
 stroyed in 1807. Captain Bishops, whose son made the statement to 
 Mr. Kellogg, cut down the dead spruces on these islands and worked 
 six weeks boiling the sea-water with fuel thus obtained, in order to make 
 salt. This was during the embargo which lead to the war of 1812 with 
 Great Britain. It is interesting to note that the bud-worm in 1878 ap- 
 peared on the same farm on which the spruces had been destroyed by 
 a worm in 1807. or about eighty years previous. 
 
 FURTHER DATA REGARDING THE HACKMATACK OR LARCH WORM. 
 
 The following facts were gathered duriug the summer of 1883 in Maine 
 and New Hampshire, and other points in Kew England and Xew York, 
 and are here put on permanent record. 
 
 We have already stated in the Entomologist's report that the larch 
 » saw-fly (Nematus erichsoniit) begins to deposit its eggs at Brunswick 
 about the 20th of June. During a journey to the Bangeley Lakes and 
 the White Mountains this saw-fly was observed depositing its eggs, July 
 1, at Phillips, where it was observed to be abundant. It was also ob- 
 served on the 2d at the Mountain View House, Bangeley Lake; also on 
 the larches along the Five-Mile Carry from the Middle Dam toUmbagog. 
 It was also observed depositing eggs in trees at Errol, N. H.; and 
 along the route from Errol to Berlin, X. H., it was observed at work 
 July 4, while a number of dead trees were noticed which had died 
 from the effects of their attacks during the preceding season. We 
 learned that they had been destructive last year in Cambridge. X. H. 
 
 Early in July these worms were also observed by us on the European 
 larch in Lawrence, Mass., and they were abundant on the European 
 larch on the grounds of Andrew Xichols, esq., of Danvers, Mass. July 
 1G, the larches along the track of the Eastern Railroad from Saco to 
 Portland were observed to be brown, having been partly defoliated by 
 the Xematus larva : some of the trees were almost entirely stripped. 
 
 During the last week in July we went from Brunswick to Rockland, 
 and thence along the coast to Eastport. returning to Brunswick by way 
 of Calais and Bangor. The larch is a very common tree in the eastern 
 portion of Maine, especially along the coast, on the islands, and in the 
 northeastern and northern part of the State. It is comparatively rare 
 west of the Kennebec River. It appears, then, that throughout the State 
 
30 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 the larch was this summer partly stripped, and a small proportion of 
 the trees were killed. The growths and forests of larch at this time as- 
 sumed a peculiar light yellowish-brown appearance, as if a light fire 
 had passed through the trees, scorching them and causing them to 
 change their color. This singular tint was characteristic of the larches 
 wherever we went. We noticed this appearance in the larches from 
 Brunswick to Eockland, at Camden and Blue Hill ; also on Deer Isle and 
 adjacent islands 5 also at and about Southwest and Bar Harbors, and 
 other points on Mount Desert Island and the islands eastward; also at 
 Mackiasport; but along the road from this town to Lubecthe larches had 
 suffered less than at other points in the eastern part of the State. At 
 Saint Stephens injured larches were observed as well as at Vanceborough 
 and the counties west of Mattawamkeag, thence to Orono and about Ban- 
 gor, and between that city and Waterville. 
 
 From Mr. C. G. Atkins, United States assistant fish commissioner, 
 we learned that the larch worm was abundant, stripping the trees, at 
 Bucksport, and also at Cherry field, Machias, and New Sharon. 
 
 General C. F. Walcott, of Boston, who, in September, 1883, spent sev- 
 eral weeks at and about the Forks of the Kennebec, informs us tbat he 
 noticed numerous dead hackmatacks in masses on Wood stream, which 
 enters Wood pond, which is a part of Moose Biver. He did not, how- 
 ever, see any dead spruce in this region in clumps or masses, although 
 his guide, an experienced boss lumberman, informed him that a great 
 many spruce trees were dying in that region. 
 
 In the Adirondack region, from Scroon Lake to North Elba and about 
 Mount Marcy, the larches were universally attacked by this worm, as 
 we are informed by George Hunt, esq., of Providence, B. I., who made 
 a journey of about 100 miles through this region in July. 
 
REPORT UPON THE COTTON WORM IN SOUTH TEXAS IN THE 
 SPRING AND EARLY SUMMER OF 1883.* 
 
 By Dr. E. H. Anderson, of Kirkwood, Miss. 
 
 'Kirkwood, Miss., June 16, 1883. 
 
 Sir : I have the honor herewith to make to you the following re- 
 port : 
 
 Having received on the 30th March my commission from the Depart- 
 ment and your instructions to visit Southern Texas to investigate Ale- 
 tia, especially as to its advent and all circumstances having an influ- 
 ence upon it, as well as to make diligent inquiry as to poisons and ma- 
 chinery for distributing them, I left home on the 2d April and reached 
 Houston, Tex., on Thursday the 5th. I remained there several days, 
 interviewing some of the more prominent citizens, especially those 
 thought to be the best informed upon the worm question. 
 
 1 soon discovered that these gentlemen were more familiar practi- 
 cally with the insects and machines and remedies for poisoning them 
 than those of my latitude, anyl in fact were old veterans in the warfare 
 waged by them against the Cotton Worm. Judge J. W. Johnson, now 
 editor and proprietor of the Houston Post, was the first whom I chanced 
 to meet. He, however, had not prosecuted the study of Aletia far 
 enough to add any knowledge to its natural history, but had paid con- 
 siderable attention to machines and poisons. I visited his warehouse 
 
 * Iu obedience to the following instructions : 
 
 Department of Agriculture, March 20, 1882. 
 Sir : I inclose your appointment for three months, beginning April 1. You will at 
 once proceed to Southern Texas and institute a thorough inquiry on the following 
 points: First. The earliest appearance of the Cotton Worm in particular sections, and 
 all attending circumstances as to character of soil, elevation, and other surroundings, 
 such as will throw light on the reason for such first appearance; second, the exact 
 condition of things in Southern Texas in reference to remedies, and the machinery in 
 vogue for applying them. 
 
 In reference to this last part of your work I want notes of experience from such 
 practical planters as you may meet — what preferences, in other words, as to remedies 
 applied and means of applying them their experience of the last two or three years 
 has led to. At the close of your work you will please make a full report as to these 
 two phases of the Cotton Worm question for that particular section. 
 
 C. V. RILEY, 
 
 Entomologist. 
 Dr. E. H. Anderson, 
 
 Kirkwood, Miss. 
 
 (31) 
 
32 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 with liim and examined his poisons and machines, in both of which he 
 is doing an extensive business. He has a large supply of pure arsenic 
 on hand, as well as a compound poison, manufactured by himself, of 
 which he sells large quantities. He presented me with a large box, 
 which I left in the hands of Dr. Eidley, near Hempstead, to be tried 
 and reported upon, which report will be duly forwarded. Judge John- 
 son's machine for spraying has been described both in your Bulletin 
 No. 3 and Agricultural Keport, 1879. He claims, however, an improve- 
 ment in the branch-pipes, and has arranged the machine to be worked 
 automatically by the pitman or by the driver. His machine is certainly 
 an admirable one, and at the reduced price of $40 is now being rap- 
 idly sold. As the season was too early for its practical application I 
 can say nothing of its operation in the field. I had an interesting in- 
 terview here with Gen. T. B. Howard. He seems to take a great in- 
 terest in the discovery of Mr. L. 0. White, of Jasper, Jasper County, 
 Texas, who professes to have originated a worm-proof cotton by pro- 
 ducing a hybrid from Jamestown weed (Datura stramonium). He 
 thinks his experiments with the seed have verified Mr. White's theory. 
 I suggested that as they belonged to two different families of plants I 
 could not understand it, but he still thinks Mr. White has accomplished 
 it, as the seed he gave him produced a plant like cotton, except that it 
 had the odor of Jamestown weed and the worms would not eat it, 
 though they eat other cotton planted side by side with it. Mr. White, 
 I learned, had offered his seed to the Department. 
 
 I also interviewed at Houston Dr. B! T. Flewellen, to whom I had 
 been referred as better posted on the subject of Aletia than any one 
 there, or perhaps in Texas, as he had made the insect his study for a 
 number of years, and had published his observations and some inter- 
 esting facts. He soon convinced me that his method of investigation 
 was careful and thorough, and that he had by experiment arrived at 
 certain facts not stated by others, and which alone could be accounted 
 for upon local and climatic causes. I held several interviews with him, 
 in order to elicit all of his views and methods, and invited him to visit 
 Fort Bend with me, which he did, and we thus had the opportunity of a 
 free exchange of opinions and discussion of the opinions of others. As 
 to hibernation of the chrysalis in Southern Texas, his experiments, he 
 says, leaves no doubt. The life term of the moth he believes to be lim- 
 ited to twelve days, twelve in summer and six in winter, as he could 
 never carry one beyond this. This would be due to climatic influence, 
 admitting it to be so. 
 
 While in De Witt County I addressed him a letter requesting an an- 
 swer to certain interrogatories. His reply reached me at Houston, and 
 from it I copied his remarks on hibernation in a letter to you. He in- 
 advertently made his experiments commence in 1868 and end in 1879, 
 when they were made in less than one year ; that is, his chrysalides were 
 l>u.t up in the fall and were carried through the following winter and 
 summer. I have sent this to him for revision. 
 
THE COTTON WORM IN SOUTH TEXAS. 33 
 
 I next went to Virginia Point, to visit Judge William J. Jones, a 
 former correspondent of the Department. My interviews with him 
 were most interesting, and were made exceedingly agreeable by his kind 
 and affable manner. His experience with Aletia has been extensive, 
 and has embraced a number of years, during which he has watched its 
 coming and progress closely, and has contended with it most vigorously 
 and persistently. He is regarded on this subject as high authority, and 
 is the originator of an improved variety of cotton, Texas sea-island. 
 
 I questioned him closely in reference to his having observed Aletia 
 larva descend by a web to the earth to pass through chrysalis. Although 
 observing that as a rule the chrysalis is made on the plant, he has nev- 
 ertheless seen it make the descent and pass into chrysalis on the earth. 
 This would be an exceptional case. Although not using scientific meth- 
 ods in his study of Aletia, he has been a close observer, and has made 
 himself familiar with its habits. He has used lights extensively, and 
 believes strongly in their efficacy. He has also experimented largely 
 with poisons, always with the result of killing the worm, and occasion- 
 ally killing his cottou likewise. This led to careful experiments, con- 
 ducted by himself, and to the adoption of the following formula, viz : 
 
 To 5 pounds of pure, unadulterated arseuic add 1 pound sal soda; boil in. a tin 
 vessel holdiug 5 gallons of water till the whole is thoroughly dissolved. If dry, one 
 quart of this mixture to he put in 40 gallons of water well strained. This will spray 
 one acre. If showery weather, add an additional pint. This will not cost over 3 
 •cents an acre, and will kill in twelve to fifteen hours. 
 
 As this place has suffered from the Cotton Worm in past years, no 
 cotton being planted there this season, it will not be amiss to mention 
 some of its topographical features. Judge Jones's plantation is located 
 on the extreme southeastern point of Galveston County, bounded on the 
 east, south, and west by Galveston Bay, and extending to its margin. 
 It forms, in fact, a peninsula, and is comparatively isolated. The soil 
 js rich, black prairie, abounding in shells and lime. The banana, orange, 
 oleander, and cape jessamine, and other tropical fruits and flowers grow 
 luxuriantly. The Gulf breeze is perpetual. The temperature in winter 
 rarely descends below 32° F. The shrubbery as well as the native 
 larger growth and matted weeds would afford admirable shelter for 
 hibernation. It is Judge Jones's opinion that the insect hibernates here 
 and does not come by immigration. He believes likewise that it hiber- 
 nates as chrysalis, but offered no facts in support of this theory that 
 could be regarded as conclusive. 
 
 The next place visited by me was the plantation of Col. L. A. Ellis, 
 at Walker's Station, Fort Bend County, situated in the Brazos bottoms, 
 3 miles from the river, having in cultivation 3,000 acres, 1,000 of which 
 was in cotton. The season being a backward one, the cotton was small, 
 and an examination furnished nothing of interest. 
 
 As the crops here are annually visited by the worm, which, in seasons 
 favorable for its propagation, does great damage, I noted the topog- 
 5135 3 
 
34 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 raphy. Oyster Greek, quite a large -stream, runs through this planta- 
 tion from north to south, and has upon its banks a varied growth of 
 native and luxuriant vegetation. Among the trees live-oak, cotton- 
 wood, pecan, and hackberry are the most conspicuous. From its serpen- 
 tine course, forming many densely shaded curves, it would afford at 
 many points admirable protection to insects or animals. The large 
 size of the gin-house and corn-cribs situated near by the creek would 
 also afford the best of winter quarters. Winter temperature and all 
 local circumstances favor the belief that Aletia passes the winter here- 
 in some form. 
 
 From this point I went on to San Antonio, finding cotton too small 
 for observation ; but, as all climatic influences seemed favorable, de- 
 termined to remain there a short time and await answers to correspond- 
 ence and then go to the most promising field. While there interviewed 
 General H. T. Bee, among others, and felt quite interested in his account 
 of his cotton experiments in Leon and Durango, Mexico. The appear- 
 ance upon cotton the first year, two hundred miles from any other cot- 
 ton, and where cotton had never been planted before, leads to the pre- 
 sumption that the worm was indigenous and had fed upon other vege- 
 tation previously. General Bee still seems to think that it is generated 
 by some peculiar condition of the cotton plant, on the evolution theory. 
 All local circumstances here, the mildness of the climate during winter r 
 the profusion of flowers furnishing nectar perpetually, and from the 
 succulent perennial vegetation, it would appear to be the paradise of 
 insects. 
 
 One marked feature here is what they call the sea-breeze, which is 
 almost perpetual and only interrupted during the prevalence of a norther, 
 which is always of short duration and scarcely worthy of the name. 
 Without this breeze their climate would be intolerably hot. 
 
 Finding no field for observation here I went to De Witt County, 
 where I heard the first bale of cotton always came from. Stopped a 
 day at Ouero to see J. 0. Hatton, to whom I had been referred. Found 
 him interested on the subject of the worm and conversant with poisons. 
 He recommends the following, viz : 
 
 No. 1. Arsenic 1 ounce; hot water to dissolve; boil until dissolved. For one 
 barrel and one acre. 
 
 No. 2. Arsenic 1 ounce; to be dissolved in hot water and put into one barrel of 
 water- London purple 1 pound to be added cold and well stirred in. To be used on 
 one acre. 
 
 He also showed me several pumps, made of block tin, but none supe- 
 rior to those exhibited and described in Bulletin No. 3. Told me Mr. 
 J. D. Anderson had requested me to visit him, as he thought he had 
 the worm. On visiting Mr. Anderson's field the first object that at- 
 tracted my attention was the rattoon sprouts from the stalks of the pre- 
 ceding year. On first examination found the eggs of Aletia much more 
 crowded than usual, and upon footstalk as well as leaf, showing a marked 
 preference for this cotton. Specimens of this were sent you at the time. 
 There were occasional stalks found in the middle of the rows, while the 
 
THE COTTON WORM IN SOUTH TEXAS. 35 
 
 new crop, then (25th April) 10 inches high, and beginning to form, had 
 single eggs only scattered here and there. The only apparent differ- 
 ence was that the foliage on the sprouts was more bushy. These 
 sprouts, I was informed, appear annually, often as early as January in 
 that locality, invariably iu March and April, though I must state that 
 I visited a field planted in cotton the previous year, about 2 miles 
 distant, and at an elevation of 20 or 25 feet above the level of the first- 
 named field, and exposed on all sides, where the stalks had not been 
 plowed up, and all were dead. 
 
 This field of Mr. Anderson's is on the Guadalupe River, and strictly 
 bottom prairie, varying from black waxy to light brown, and all ex- 
 tremely fertile. The field extends from the river on the west to the 
 hills on the east, where the land breaks off into upland wooded prairie, 
 of lime and gravelly geological formation. The hill skirting the field 
 has at its base a luxuriant undergrowth, among which may be fouud 
 many native brilliant flowers, and over which flourishes the live oak 
 with its parasitic moss, the cotton-wood, hackberry, and others native 
 to the clime. The country to the south along the Guadalupe is low 
 and level, while to the southeast it presents rolling wooded prairie. 
 Here the gulf breeze predominates, Indianola on the Gulf being but 27 
 miles distant, and makes the climate delightful. Here, as reported to 
 you in detail, I found the first brood of Aletia in all its stages, except 
 moth, though knowing the moth to be there by the freshness of the 
 eggs, unless all of that brood had perished. Mr. Anderson informed 
 me that previous to the appearance of the worm a number of the chrys- 
 alids had been plowed up, and that this was a matter of annual obser- 
 vation, and he had no doubt that the first brood of worms came from the 
 moths that issued from the chrysalids plowed up in March and April, 
 and that the worms often appeared as early as the 1st of April. 
 
 Learning how early the old cotton-stalks often sprouted, the early 
 appearance of the worm, the mildness of their winters, the thermometer 
 never falling below 19° F., the porous and loose character of their soil, 
 and as the boll -worm does not affect their cotton, and could not be mis- 
 taken in chrysalis for Aletia, it would seem highly probable that the 
 chrysalis would survive their short winter in that locality. Neverthe- 
 less, after the most diligent search 1 could not procure one, nor could I 
 rely sufficiently upon the accuracy of their knowledge of the chrysalis 
 to accept their statements as conclusive j and if the chrysalis did sur- 
 vive the winter up to the 1st of April, I was there too late, as all had 
 emerged as moths. 
 
 I visited other places in the neighborhood, but this serves as a type 
 for all. 
 
 Mr. Anderson had constructed under his supervision a machine for 
 spraying, that seemed to me to possess advantages over any other that 
 1 have seen, both as to its capacity to spray a larger area in a given 
 time and for cheapness. As he has promised to furnish me a draft I 
 will not attempt a description. I will here copy his recipe for poisons : 
 
36 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 Early in the season, when cotton is young and tender, one ounce of arsenic boiled 
 in one gallon of water five minutes and then put in a barrel of cold water will de- 
 stroy the worms. But in order to make it more efficient, add one-fourth pound Lon- 
 don purple, mixed up in cold water. This will go over an acre of land when properly 
 applied. When the cotton is older and the worms more numerous double the poison ; 
 no danger of hurting the cotton. The worms are about nine days hatching, and as 
 iheavy dews and rains will wash off the poison it must be applied every three days in 
 jhatching season! The proper time to commence poisoning is when the millers or 
 moths are depositing their eggs. They can be seen at work after sunset and before 
 sunrise. 
 
 I regard as important this gentleman's views, as be is a thoroughly 
 practical man, and has the energy to execute as well as the intelligence 
 to formulate his ideas methodically. 
 
 From this point I went to Fort Bend on the Brazos, and remained sev- 
 eral days with Colonel Cunningham, adjoining Colonel Ellis's, the two 
 plantations cultivating 2,000 acres of cotton. This was early in May. 
 I inquired for the largest cotton, and on visiting the held found a few 
 worms, specimens of which were sent to you. This was the first brood, 
 and unsuspected until found by me. This field was located near Oyster 
 Creek, and had upon it the decaying trunks of live oak, still covered 
 with moss, and pecans. It was designated as mulatto land, and very 
 rich, lying between Oyster Creek and the Brazos. The general features 
 were such as observed upon Colonel Ellis's plantation adjoining. The 
 mildness of winter temperature here, the many secluded spots, the abun- 
 dance of native perennial flora, and the almost perpetual southern gulf 
 breeze, as well as the great mass of stubble, rendering the soil extremely 
 porous, would all favor the different theories entertained as to Aletia. 
 While passing through many portions of Southern Texas, of both bald 
 and wooded prairie, now devoted to ranches, I could not but pause 
 to admire the profusion of wild flowers of infinite variety, intermingled 
 with native grasses, giving an additional charm to the landscape, and 
 furnishing food for both insect and animal. Here the moth could find 
 a congenial winter home, if nature has endowed it with such longevity. 
 
 Jsfext visited Hempstead. As I have reported to you from that point 
 in detail in my correspondence, will now give a mere synopsis. Found 
 the first brood there on the highest point in the field, where bone phos- 
 phates had been used as a fertilizer, and where cotton was then, May 
 14 forming. This plantation was upland wooded prairie, 3 miles from 
 the Brazos, at an elevation of 30 or 40 feet above river, and about 70 
 above sea level. The soil may be called sandy loam, and quite fertile. 
 The size of the cotton had much to do with the presence of the worm, 
 but there were, perhaps, other agencies that aided in hastening it there. 
 It was found near an abrupt break on the crest of the hill which had 
 become overgrown with rank vegetation, and which sheltered a portion 
 of the field under its lea. Here either chrysalis or moth would have 
 been protected against the inclemency of winter. Here, likewise, all 
 the surroundings were favorable for the preservation of insect life. It 
 is a coincidence not without significance in my experience that the first 
 

 THE COTTON WORM IN SOUTH TEXAS. 37 
 
 appearance of the worm here, as well as elsewhere, was coincident with 
 plowing while the land was wet and temperature ruling high, thus induc- 
 ing an abnormal temperature by disturbing natural capillarity. The 
 present temperature, May 15, corresponds with the temperature of Madi- 
 son County, Mississippi, in August, when worms make their appearance 
 there. I here first tried the experiment of burning molasses placed in 
 a pan over a lamp chimney, placing on the ground another plate con- 
 taining molasses and coal-oil. First night caught two moths, second 
 night caught ten. Would recommend iu all cases, the burning of mo- 
 lasses, as it is my belief that the aroma is more attractive than light. 
 
 These were the first moths caught, though lights had often been pre- 
 viously used. Will here remark that every field I visited in Texas was 
 infested with ants, varying from the largest to the smallest size, and 
 differing in color. They are great pests and not only damage stands 
 of cotton by cutting it down, as the cut-worm does, but one species 
 sometimes excavates considerable areas with its subterranean houses, 
 and thereby ruins both corn and cotton. They doubtless, from their 
 predaceous habits, destroy a great many worms, and the farmers say 
 they do. 
 
 My next visit was to Columbia, Brazoria County, where I inter- 
 viewed several of the most intelligent citizens, and visited a field on the 
 Brazos in company with Col. John Adriance, an old and highly intel- 
 ligent planter. Here I found the worm on cotton near the river bank, 
 specimens of which I sent you, though they had doubtless webbed up 
 before reaching you. This brood was about to pass into chrysalis, as 
 it was at Hempstead, showing it to be about contemporaneous. No new 
 features to be observed here. The opinion prevails that the insect win- 
 ters here. 
 
 I next visited Judge William J. Jones in quest of Anomis exacta, but 
 had a fruitless search, as he planted no cotton this season. As the 
 specimen sent to you by him, two years ago, was among a lot of chrys- 
 alids, gathered both on the Brazos and at his home place, and as he had 
 never seen the larva of exacta, to know it distinctly from Aletia, he would 
 have been unable to identify it. 
 
 Next proceeded to Columbus, on the Colorado. The soil here was 
 lighter colored and more sandy than on the Brazos, in fact so loose as 
 to be drifted by the prevailing winds. It nevertheless possesses great 
 fertility. I found cotton here of good size and forming, and soon found 
 the worm. Saw here the same topographical features and physical 
 agencies as elsewhere that seem to influence the life of Aletia. 
 
 Went on to San Antonio and saw near Seguin in an upland field near 
 the Guadalupe Eiver some of the largest cotton 1 met with, but saw 
 there nothing of interest to report. 
 
 Would have continued my observations in Southern Texas until tlie 
 end of June, but as I found the insect wherever I went, as far north 
 even as Hempstead, I determined to return to Mississippi, to watch its 
 incoming there, as that is still an unsettled question. 
 
38 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 My conclusion is that the southern belt of Texas, as high as 30° 
 north latitude, offers Aletia a secure winter retreat, and that it there 
 passes through its different stages under the influence of temperature ; 
 and although cotton is its preferred food, yet it is capable of being sus- 
 tained upon other plants, selected by the instinct of the parent moth, 
 until the incoming of cotton. 
 
 The fact has been established that it was indigenous and perennial in 
 the Bahamas, and from my observation, and all information gathered 
 in Texas, I think the same rule would apply there. 
 
 Finally, regarding yourself as the highest authority upon this subject^ 
 as well as all others connected with your Department, I can reconcile 
 your last utterance upon the hibernation of Aletia, as far as facts are 
 concerned, with the theory advocated in this report and deducible from 
 all information gathered in my recent visit to Texas. You say " there 
 is nothing more fully established now than that the moth hibernates 
 principally under the shelter of rank grass in the more heavily timbered 
 portions of the South ; n and also that " you had been able to obtain the 
 moths during every month." The only difference is a perpetuation of 
 the cycle of transformation instead of a true hibernation in that latitude. 
 
 I have the honor to be, with sentiments of high respect, 
 Yours, truly, 
 
 E. H. ANDERSON. 
 
 Prof. G. Y. Eiley, Entomologist. 
 
EXPERIMENTAL TESTS OF MACHINERY DESIGNED FOR THE DE- 
 STRUCTION OF THE COTTON WORM. 
 
 Report by W. S. Barnard, Ph. D.* 
 
 U. S. Department of Agriculture, 
 Entomological Division, 
 Washington, B. G\, August 15, 1883. 
 Sir : Under your direction I have prepared and hereby submit the 
 following report on the experimental tests made during the last three 
 weeks near Selma, Ala. 
 IfcespectfuUy, 
 
 O. V. Eiley, Entomologist. ■ 
 
 W. S. BAENAED, Assistant. 
 
 IREFORT. 
 
 The Cotton Worm machine described in the annual report for 1881-82, 
 and now subjected to field tests, is shown to be suited only for cotton 
 so planted that the rows are spaced apart very equally, since it lacks 
 adaptability to the usual great differences of interspaces between the 
 rows. Unfortunately, nothing very closely approaching ideal straight- 
 ness of rows or equality of width between them can be detected in the 
 South, even in such fields as are said to be " planted perfectly true/ 7 
 
 * Letter of instruction. 
 
 Department of Agriculture, 
 
 Division of Entomology, 
 
 July 14, 1883. 
 Sir : You will proceed to Selma, Ala., on the 18th. of this month to carry out in detail 
 the verbal instructions which I have given you. These are, chiefly, to take with you 
 or send all the machinery necessary to put together and operate the spraying machine 
 illustrated on Plate IX of our last annual report. You will test this machine thor- 
 oughly, in order to settle by experience the numerous points that have not yet had 
 practical field demonstration. Thus, the most satisfactory form of nozzle, whether 
 for London purple, Paris green, or kerosene emulsion, the number of rows it is found 
 best to spray at once, the relative effects of finer or coarser sprays, and particularly 
 the effect of petroleum, etc., etc. Be particular to ascertain the actual cost and 
 actual area covered by a given amount of liquid. You will spend no time in testing 
 other devices or modes of poisoning. 
 
 ******* 
 Respectfully, 
 
 C. V. RILEY, 
 
 Prof. W. S. Barnard, 
 
 Assistant, Entomological Division. 
 
 Entomologist, 
 (39) 
 
40 BULLETIN NO. 3, DIVJSION OF ENTOMOLOGY. 
 
 In the more evenly disposed cotton, stiff fork apparatus, made light and 
 shorter, to supply only four rows at each drive, and hung loosely upon 
 hooks instead of eyes, without the ratchet lever elevator, and capable 
 of being easily slid by hand to the left or right, as infringement on row 
 crooks from time to time required, proved susceptible of use with due 
 watchfulness ; but the eight-row machine was too heavy to be thus 
 shifted by hand, and being stiff-backed with rigid descending pipes, no 
 eight consecutive rows could be found regular enough to be callipered 
 for much distance by this device. The inflexibility also prevented con- 
 form ability of the apparatus to inequalities of the ground, an eleva- 
 tion straining hard on one descending pipe, lifting the others from the 
 ground, etc., and the light, flexile, jointed nozzle-arms, being borne 
 upon severely by the stiff pipe system, soon became impaired, whereas 
 they had formerly and have since worked well oh the yielding stem- 
 pipes of the adjustable machines which were tested at the time of the 
 Atlanta exposition, as well as in these last experiments. For under- 
 spraying, this old-fashioned, stiff, cross-pipe system is shown to be wrong, 
 as originally foreseen, unless some power can be brought to bear to en- 
 force a system of greater straightness and equality in planting cotton. 
 A considerable amount of the irregularity in rows has been attributed 
 to the " constitutional perversity and crookedness of the nigger," ap- 
 pearing from the bad execution of his instructions. But even if this could 
 be corrected it is not the matter of vital importance, for the planter 
 himself, as well as the field-hand, is guided by a natural principle 
 which will always control and stand against any contrary theoretical 
 or mechanical rule. According to " the strength of the ground," the size 
 of plant it will produce, will the rows run wider or narrower in any par- 
 ticular " cut " or part of a " cut." This accounts for the diverging and 
 meandering rows, for the many " cuts " of a plantation differing among 
 each other in their row-widths as observed everywhere. 
 
 As to conveyances for underspraying apparatuses, it was found not 
 desirable to use a wagon or cart of ordinary width (5 feet) in cotton 
 only 3 feet wide or less, because of the much injury done to the plants 
 by the wheels. Most of the cotton in the Garolinas, Georgia, Ten- 
 nessee, Alabama, and Mississippi comes within these dimensions ; hence 
 a shorter special axle for the cart or wagon wheels should generally 
 be employed in any conveyance for the apparatus. But where se- 
 verely threatened by worms the ordinary wagon or cart will do less 
 damage than the pest in any kind of cotton; and it is on this ac- 
 count that wagons are already used to a considerable extent for trans- 
 porting poison and broadcast spraying devices in all kinds of fields. 
 Mr. A. T. Jones, near Selma, uses four mules on his heavy spraying 
 machine. But ordinarily the common plantation cart will be found the 
 most suitable vehicle. This or the lumber wagon will straddle row& 
 4 feet apart or over without injury to the plants except in turnings 
 and that is surprisingly small, being least with the cart. With shafts 
 
TESTS OF MACHINERY FOR POISONING COTTON WORMS. 41 
 
 placed in the usual position the mule must travel on a row to have the 
 two wheels straddle it properly, and this not practical. I obviated the 
 objection by a pair of rough shafts set to one side, one shaft coming 
 from the center of the cart and the other standing outside of the wheel r. 
 thus the mule is held nearly in front of one wheel and midway between a 
 pair of rows. In practice it is shown that the slight side-draft caused 
 by this arrangement amounts to almost nothing. And it should be re- 
 membered that it is common in the North to use side shafts on sleighs r 
 buggies, &c. The apparatus is easily pulled by one mule, which should 
 travel preferably in front of the right wheel. 
 
 The personal labor required is such that the pumper may also drive 
 and keep an eye on the machine behind. It is most convenient when 
 the stirrer, pump, and barrel are placed near the left side of the cart with 
 the lever or pump-handle standing crosswise. The operator then only 
 looks to the right and the left instead of having to look backward. ' The 
 mule, accustomed to working in cotton, follows between the rows as a 
 rule without being guided, and the pumper is free to turn him at the 
 ends. In this manner one man can use the apparatus alone without 
 working any harder than he should. Still, it is generally preferable te 
 have a boy attendant to assist at times, and where a larger pump with 
 a very wide system of pipes to supply a large number of rows is engaged 
 it will be well to have two men to take turns at pumping in cases where 
 a pump motor is not provided. With such labor, the adjustable under- 
 spraying machines which I have devised and shall notice below were 
 operated, the best hand being a mulatto who worked for fifty cents a 
 day, which is a common price for cotton-field hands. Thus the labor 
 cost is small, and one or two men with a machine can do much more and 
 better spraying than a large gang does by ordinary methods. 
 
 The rapidity depends altogether on the width of the pipe-system, or 
 number and width of rows supplied, or the size of the cotton, of the noz- 
 zle-discharges and of the pump, on the velocity or pressure applied, and 
 on the speed of the mule. It may vary with any one of these details, I 
 had only one pump, this rather small, and could not try the effects of 
 different sizes. There was not much diversity in the cotton and it was 
 below medium size. At Selraa, I labored under difficulties from bad 
 workmanship, from lack of available mechanics for constructing the 
 devices, on which account there were bad joints in the apparatuses, which 
 leaked some, and which would loosen and at times come apart when 
 high pressure was applied, thus causing stoppages in the work. Under 
 the circumstances the question of time and scope could not be very sat- 
 isfactorily tested ; but as to the very fine small sprays for small cotton 
 the following conclusions result from this experience : 
 
 Taking nearly average sized cotton, and the parts of the apparatus of 
 medium capacity, an acre and a half was poisoned iu one-half an hour ? 
 24 feet wide being poisoned at a single drive, and the rows were quite 
 short. Twice this rapidity can be attained. 
 
42 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 The quantity of liquid and poison used also depends on the various con- 
 ditions stated as determining the rapidity. The amount of liquid to the 
 acre, as near as could be estimated under the circumstances, ranged 
 from 10 to 40 gallons, according to the size of the spray-discharge and 
 of the cotton. The quantity of poison is in direct proportion thereto, 
 being one-eighth to one-half a pound of London purple, or one-fourth 
 to four-fourths of a pound of Paris green to the acre. 
 
 The stirrer-pump device is a most perfect thing for the purpose and 
 gave the greatest satisfaction. This contrivance is described and illus- 
 trated in the annual report for 1881-'82 (pi. ix, pp. 159-161). The pump 
 has heavy metallic valves, and its piston-head has no soft packing, so 
 there is nothing about it that can get out of order. Yarn packing is 
 used in the stuffing-box at its top. Being double acting it throws a 
 strong and constant stream. Only one trunnion-eye need be moved? 
 and a single iron wedge, instead of two, is sufficient for setting it. The 
 wedge has on its head a catch whereby it is easily pryed out, and an eye 
 oy which it is chained fast to prevent losing it. In place of the wooden 
 stirrer bar formerly employed I have made an iron one having a spring 
 at the middle to clamp snugly in the eye at the bottom of the pump. 
 This will not weaken with age or break. The cord or chain for pulling 
 out the bar is not essential, as by having the end buug-hole of two 
 inches diameter a pair of tongs or pinchers can be inserted to take hold 
 of the end of the stirrer and extract it. The main hose or pipe has a 
 screw union, by which it is easily separable from the pump. 
 
 The descending pipes between the rows should have flexion and tor- 
 sion in their joints or segments or hangings. The ground beneath 
 the cotton-rows is highly ridged, and the mid-furrow between each 
 pair of rows is deep. The ground thus formed operates upon the 
 lower parts of each descending pipe or its appurtenances, when suita- 
 bly shaped, so as automatically to guide the pipe and its nozzles 
 between the rows, and to follow any crooks therein even when the 
 conveyance is not driven in conformity with such irregularities. This 
 automatical adjusting is allowed to a large extent even when the 
 top of the descending pipe is firmly or non-adjustably attached, pro- 
 vided that the descending pipe be flexile in some part of its course. 
 "This was shown in the earlier flexile forked machines which were 
 tested for this Department near the Atlanta exposition. For the ob- 
 ject in question the descending pipe may be flexile throughout, but it 
 is more commonly preferable to construct this pipe of stiff segments 
 having one or two flexile joints, or very short hose segments; one at 
 its top, and another at about two-thirds or one-half of the way down- 
 ward therefrom. It is also generally best to make these flexile seg- 
 ments or joints of three-ply or two-ply hose, and only of such length 
 as to allow them to bend like knee-joints, and to suffer a semi-rotation 
 or semi-torsion. This construction prevents the trailing-fork or other 
 end part from getting turned upside down, or from remaining in wrong 
 
TESTS OF MACHINERY FOR KILLING COTTON WORMS. 43 
 
 attitude after dragging among or over the plants in turning, and it 
 always tends to spring or throw the nozzles back to such positions that 
 they deliver a properly-directed spray into the plants. Where* torsion 
 without bending is desired in these flexile places a rod extending 
 through the interior may be employed somewhat as described for cross- 
 pipes and nozzle-arms in the special report of the United States Ento- 
 mological Commission that has been prepared. The arrangements and 
 constructions referred to have been carefully tested this season to cor- 
 roborate the results of previous experience. The principle involved 
 is simple and practical in its operation, having been tested at Atlanta, 
 and again this year at Selma, Ala. 
 
 The flexile nozzle-arms of the Y-shaped trailing forks which were 
 originally designed with flexile stems worked satisfactorily thus at- 
 tached; but when these fork-arms were tested on a stiffly hung pipe, 
 the spring-rod inside soon proved too weak. The strong pendant 
 T-forkswith curved or sloping side-arms made stiff proxiinally, and hav- 
 ing 3-ply hose for their distal half or two-thirds, stood severe usage by 
 all methods, since they were made of stronger tubing and had much 
 stouter spring-rods within. The spring-rod in each arm had its distal end 
 soldered in a short piece of tube abutting against the stem of the nozzle. 
 Forks of whatever construction will be guided more by the ridges if 
 the arms extend in a somewhat upward direction before becoming hori- 
 zontal at the ends beneath the plants, as the median part of the fork 
 can then sink into the mid-furrow and be guided by its sides. Prob- 
 ably nothing better than the pendant Y-forks and T-forks can be de- 
 vised for spraying upward through the center ol the plant. An addi- 
 tional pair of short arms or of nozzles may be used with advantage to 
 discharge from near the median line in divergent direction upward 
 through the tops of the plants. The simplest plan is to join these or 
 the simple eddy chambers directly to the stem-pipe or its extension, low 
 down. Such nozzles may be attached side by side, or in what I call a 
 tandem gang. This is a series of short tubes coupled end to end, each 
 bearing an eddy-chamber discharge. These may be rotated on their 
 axes and so are adjustable to different angles. Those who prefer to 
 underspray the top of the plant and care less for its base will find the 
 tandem arrangement by itself the best device for that purpose for throw- 
 ing from the ground, though the forks answer as well when elevated, 
 and may also be used beneath the base. 
 
 The eddy-chamber nozzles seem the best sprayers available for ap- 
 plying the poison. These nozzles have been tested this season with the 
 discharge-hole of various sizes, from one-sixty-fourth to one-eighth of 
 an inch diameter. The smaller orifices give the finest sprays conceiva- 
 ble. Indeed, with high pressure, the spray vanishes into vapor and 
 steam which does not fall, but rises to seek the clouds. From this the 
 damp particles of poison powder must separate and fall. But with or- 
 dinary pressure too fine a spray is not attained. 
 
44 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 With the fine strainer on the suction end of the pump, clogging mate- 
 rials in the water are prevented from entering the pipe system or the 
 nozzles. Additional smaller gauze strainers were attached to the ends 
 of the metal tubes in one set of pipes. They keep out dirt, etc., when 
 the pipes are separated, but may not prove of importance. The proper 
 method is to have a completely closed system, with folding joints that 
 never need to be separated, so the whole can be folded into a small com- 
 pact package for transportation by rail or to the field. Such a system 
 has given great satisfaction by its convenience, as well as by allowing no 
 obstacles to enter the nozzles. In spite of the most perfect precautions 
 clogging will occur at the outset or before high pressure is attained,, 
 chiefly from the scales of iron separating from the interior of the pipe 
 as loosened by rusting and jarring. With the finest nozzles (one sixty- 
 fourth inch discharge) these seem to cause no more difficulty than with 
 a standard beveled one-sixteenth inch discharge. The nozzle faces may 
 be removed to let out any obstacles which with low pressure are apt 
 to clog the outlet and stop the internal rotation. But a high pressure 
 should always be used, and when this is once up the outlet may be 
 pricked with a pin, and it will discharge with an almost explosive force, 
 instantly starting an inconceivably rapid internal rotation, which, while 
 sustained with due pressure, will by its centrifugal action prevent any 
 particle from again finding the center of rotation from which the dis- 
 charge takes place. This is especially true of the smallest nozzles? 
 having an outlet just large enough to admit the insertion of a pin. As 
 previously set forth, the inner edge of the outlet should generally be 
 square or sharp. In the eddy chamber a great hydraulic pressure is 
 generated, so great that by thumb pressure the discharge cannot be 
 stopped. The power therein accumulated under high pressure is suffi- 
 cient to cut through and disintegrate any obstructing particles or frag- 
 ments, except those of the hardest kind, which are so heavy as to fly off 
 from the center by their weight and momentum when the velocity 
 of rotation is once up or quickly starts. 
 
 The top adjustments of the descending pipes are very important. 
 These tops may be variously hung, combined, or constructed. A knowl- 
 edge of the irregularities of ordinary cotton fields, such as appear chiefly 
 in crooks of the rows and in variations of width between them, preveuts 
 the idea of a stiff, unadjustable attachment of the tops of the pipes, 
 which must travel between and more or less against the rows. Con- 
 formity to all inequalities of the ground, its numerousups anddowns, its 
 dead furrows, ditches, stones, and stumps, should likewise be attained. 
 It must also be evident that a large, stiff apparatus is difficult to haul 
 about, as it cannot be taken entire through gates except with much la- 
 bor. Of course it is possible to disjoint the parts beforehand, and then 
 screw them together tight afterwards when the field is reached. This,, 
 however, is hardly practicable. In fact the separating and joining of 
 stiff metal joints by field hands is a failure. Plumber's tools are neces- 
 
TESTS OF MACHINERY FOR KILLING COTTON WORMS. 45 
 
 sary for this purpose. The field laborer of the South screws up the joint 
 too tight, too loose, or in such form as to spoil the screw-threads. Again, 
 the joints become rusted together and a vise must be engaged. The 
 stiff system also requires that very heavy pipe be used, as the leverage 
 on long pipe arms enables them to suffer great strain, to become broken 
 off easily at the end where the thread for the joint is cut, whereas with 
 flexile joints no leverage power but only tensile strain can be brought to 
 bear. In the latter case very light tubing can be employed with economy 
 in material, cost, labor, and salvage of cotton. Moreover, only by such 
 light flexile apparatus can any considerable number of rows be treated 
 at once from beneath. These facts have been substantiated by tests of 
 stiff and of flexile apparatus this season more fully than they were by 
 the Atlanta tests, in which one light machine undersprayed eighteen 
 rows of cotton, a strip twenty yards wide, at a single drive. The tests 
 this year have been not only of stiff connections, but also of the con- 
 structions whereby adjustability of the descending pipes is effected au- 
 tomatically and by hand. These have already been noticed above or 
 in the previous reports in so far as they pertain to the stem or body of 
 the pipe or its distal appendages ; hence, next in order may be considered 
 more specifically and in natural sequence the construction and arrange- 
 ments of the tops of these pipes as planned and tested by me: 
 
 I. The stiff hanging tubes have been tried, as already set forth, in 
 Arm union with a stiff back-pipe or cross-pipe such as appears in many 
 of the patented sprayers, as Johnson's, Daughtrey's, etc., while suffi- 
 cient objections to this arrangement for underspraying have already 
 been presented. It is the first construction which naturally suggests 
 itself to any plumber or other mechanic, but presents no special adap- 
 tation for the purpose, as has been shown this season and previously. 
 
 II. The extremest opposite construction to the foregoing is attained 
 by having radiating flexile tubes from the main to the descending pipes, 
 instead of a straight and stiff cross-pipe. By this arrangement the 
 hanging pipes are swung apart or nearer together independently, and 
 set on a cross-bar or on diverging bars, at spaces to suit rows having 
 different courses or widths. 
 
 By way of variation the tubes may radiate only for a part of the 
 -distance, and for a space run close beside each other along a supporting 
 bar before reaching the descending parts. The parts upon the support 
 are preferably of metal, and slide readily in peculiarly locked hooks, as 
 simple, easily separable attachments, specially devised for this purpose. 
 Where the descending parts have flexibility to some extent they may 
 drag in the cotton in turning, as stated above. It is shown that they thus 
 do no noteworthy harm to the plants; also that they themselves do not 
 suffer injury. This flexile construction is simple, and generally preferable 
 in combination with the flexile connectives between their tops. But 
 should any prefer that the hanging parts be elevated above the plants in 
 turning, this is easily done. For such purpose, and to shorten the lever- 
 
46 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 age in lifting, the descending part should preferably have a flexile joint 
 just below midway, to bend like a knee when the lift is made. Tbe upper 
 half of the descending pipe is rigidly continuous with the stiff parallel 
 part, forming therewith a bent angle, while the proximal end of the 
 parallel part is turned backward as a hollow tubular crank, having its 
 handle-end communicating with one of the radiating or slack hose pipes? 
 which allow the stiff parts to be shifted laterally. By swinging the back - 
 ward crank-shaped part of the pipe over to a forward position, into a 
 catch, the hanging parts of the pipe are swung upward above the plants 
 and sustained there. This season two, three, and four of these crank- 
 ended pipes were tried, combined with the same bar. When the 
 horizontal part of such a pipe is short or not too heavy it will be shifted 
 laterally automatically by the trailing part by the method already 
 noticed ; but where the pipe is too heavy or rough to slide easily the 
 hand of the pumper must occasionally be used upon the proximal or 
 crank end to shove the pipe into such position as will suitably adjust 
 the nozzles to the rows. 
 
 In the divergent arrangements thus indicated the shifting or lateral 
 adjustability is permitted by opening or shutting the angles between 
 the diverging tubes, and this is, in its operation, in some sense, analo- 
 gous to taking out and letting out slack in the connecting parts between 
 the nozzles. By a surplus amount of inflection or slack, by joint or other 
 flexibility, in a tube or tubes connecting the tops of any two neighbor- 
 ing pipes, whether right, left, or mesial, in a system, the two can be sep- 
 arated, approximated, or independently adjusted to the extent desired. 
 By this method the stiff pieces sliding on the bar and supporting the 
 pipe-tops can be short, light, and arranged somewhat end to end,*joined 
 in tandem order, with intermediate flexile crooks that may be extended 
 or shortened as operated by the automatic action of the trailing branch. 
 These tandem gangs of light, sliding segments for supporting or sup- 
 plying the tops of the pipes, have stood a satisfactory test in the cot- 
 ton this season. 
 
 Such parts may also be arranged on bars having a slope backward 
 or downward, as on the A-frames, or other kinds of frames, or they can 
 be set in a somewhat zigzag manner on a cross-bar. This use of a 
 slope gives certain advantages, and characterizes some varieties of 
 apparatus closely related to that just noticed. In these, the pulling 
 of the downward pipe, by its gravitation or friction, causes its top 
 piece, which has an inclination to slide on the slope, to travel in a 
 diagonal direction along on the support and across the rows ; but work- 
 ing in opposition thereto is a pull-line or cord having one end on a 
 winder near the hand of the pumper. Letting out the line allows the 
 pipe to travel farther along the slope, and winding it up draws the pipe 
 in the opposite direction. Thus any pipe at a distance can be easily 
 shifted and set at a point to suit by letting out or drawing the line. Thik 
 principle I have executed in three ways : In the first, the supply tube 
 
TESTS OF MACHINERY FOR KILLING COTTON WORMS. 47 
 
 supports the bung-pipe and slides in eyes situated diagonally with re- 
 ference to the hung-pipe. In the second, the pipe-top is supplied by a 
 flexile piece of hose, and is supported by a long slide-rod on one or 
 two of its sides, and inserted through loose eyes placed diagonally from 
 the course of traction, as in the foregoing case. In the third instance 
 the top is similarly supplied by a hose, but is hung by a peculiar locked 
 hook, eye, or loop which glides loosely on a stiffly-set diagonal bar. The 
 simple wooden A-frame answers, and a series of small sloping metal bars 
 of gas-pipe were arranged on a wooden cross-bar. This device worked 
 well. Many kinds of winders would apply, but a simple plan is to wind 
 the small rope or cord around a pair of large eye-screws placed 3 inches 
 apart. The set line can be attached at any point along the sliding 
 parts. Behind the proximal end of the range, through which any 
 pipe-top is to be allowed to slide, the line may pass through a large 
 screw-eye and thence to an extension of the pipe-top above the axis on 
 which it is hung. Then the pipe may be drawn to this place, and by an 
 extra pull its top will be brought down to the eye and the lower parts 
 of the pipe will be tilted upward above the plants for turning, when this 
 feature is desired. 
 
 Concerning the use of kerosene upon cotton, the following should be 
 stated : About 10 gallons were applied, half undiluted and half in 
 emulsion variously diluted. The undiluted petroleum destroyed about 
 .10 per cent, of the foilage sprayed by it. The undiluted milk-kerosene 
 emulsion ruined only about 2 per cent., and this diluted injures less and 
 less according to the attenuation, but all treated was injured to at least 
 a slight extent. The sprays were hardly satisfactory, as, the tubing 
 would not permit the high pressure necessary for a very fine mist, and 
 the indications are that with the finest spray the strong kerosene and its 
 slightly diluted preparations may possibly yet become used, in proper 
 hands with great caution, upon the crop, but additional experimental 
 tests are needed. 
 
 The apparatus taken, with the different machines constructed at Selma 
 and overcoming the objections herein set forth, have been shipped to the 
 Department. 
 
 The leading conclusions from the experiments upon the special points 
 in my instructions may be extracted from the above and briefly sum- 
 marized as follows : 
 
 At Selma, I operated the machine taken from the Department and 
 tested the points in question, so far as circumstances permitted. The 
 distinctive feature of the machine, its stiff supporting pipes, unfitted it 
 for the work to be accomplished. As fields could not be found having 
 rows practically of the same regular width as the spaces at which the 
 downward pipes were held stiff by their supporting pipe, that permitted 
 no independent lateral adjustment of the tops of the hanging pipes with 
 reference to each other or to the rows having different or varying widths, 
 this vital impediment at the outset frustrated its use and the obtain- 
 
48 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 merit of results dependent thereon. The tests showed that with a pipe- 
 system, without lateral adjustability at the top, very few rows, usually 
 not more than four, can be treated at once. In this small form the whole 
 pipe system can occasionally be moved laterally by hand as the row 
 irregularities require it. 
 
 The forks were operated dragging upon the ground, and also set at 
 different heights. The ratchet for vertical adjustment subserved this 
 purpose satisfactorily. Where it is desired to spray the base and interior 
 of the plants from beneath, the nozzle arms mast necessarily be car- 
 ried near or on the ground, and with medium to small cotton this method 
 also sprays the tops sufficiently well, but if the growth be heavy and 
 dense it proves better to set the forks higher for more thoroughly poi- 
 soning the tops. 
 
 The stirrer pump worked admirably ; but a larger pump of the same 
 kind was necessary to treat a greater number of rows, to ascertain how 
 large a number it is possible or advisable to spray at a time. While the 
 large pump was being constructed and shipped the time limited by my 
 orders expired. 
 
 Four rows may be set as the number it is most practical to treat at a 
 time with the kind of machine in question. 
 
 The springs of the fork-arms should be larger and have a longer bend 
 than in the samples taken, since the unyielding attachment of the stem, 
 pipes to the stiff supporting pipe above throws on the springs much 
 greater strain than occurs in the machines having descending parts 
 hung to operate independently of each other. 
 
 Until my time had expired worms were not abundant enough to study 
 the effects on them of the coarser and finer sprays applied, but the 
 coarser spray was more injurious to the foliage with poisons, and still 
 more so with petroleum. 
 
 The standard form of eddy-chamber nozzle was used with discharges 
 of different sizes. The smallest discharge holes, of ¥ X T to y 1 ^ of an inch 
 diameter, with very high pressure, gave the most satisfactory results. 
 
 The " actual cost, and the actual area covered by a given amount of 
 liquid," vary greatly with the width between the rows, the sizes of the 
 sprays and of the plants, with the number of nozzles, with the amount 
 of pressure applied and the volume capacity of the pump, the velocity 
 at which the machine is drawn, etc. On account of the complexity of 
 the question, and especially because of leakage from imperfect pipe- 
 joints and for want of other and larger apparatus, the question could 
 not be solved with any exactness. 
 
€N SOME OF THE NORTH AMERICAN COSSIME, WITH FACTS IN 
 THE LIFE HISTORY OF COSSUS CENTERENSIS Lintner. 
 
 Bv James S. Bailey, A. M., M. D., Albany, N. Y. 
 
 Cossus centerensis (Plate I) was discovered by Dr. Theodore P. Bailey 
 in 1877. For many years previous I had observed that many trees of the 
 Fopulus tremuloides had perished from some cause then unknown. The 
 central shoots of other trees of the same species were dead, and it would 
 only require a few years to finish their destruction. Perforations were 
 found in the trunks of these trees, some of recent date and some over- 
 grown with bark, leaving the cicatrices plainly visible. 
 
 In July, 1870, a brittle pupa-case of the Cossus was found projecting 
 from one of the openings, which gave the first clue to the, nature of the 
 borer and destroyer of the timber. 
 
 On the 10th of June, 1877, a fresh pupa-case was discovered, and on 
 the 14th of the same month the first Cossus was captured, resting upon 
 the same tree trunk. Every season since this capture the Cossus has 
 been taken, but in some years in greater numbers than others. 
 
 The Cossus usually comes forth between the setting and rising of the 
 sun, and when the trees are visited daily the protruding pupa-cases left 
 behind by the escaped imagines informs the collector how many of the 
 nsects he may expect to find. 
 
 Their color similates so closely the color of the bark of the trees that 
 it requires good eyes and very close observation to find the moths. 
 One unaccustomed to collect them might view an infested tree for a 
 long time and not find a Cossus, when several would be discovered by 
 an expert. An uneven protuberance on the bark, or the short stump 
 left of a deca3 r ed broken limb are favorite resting places for the insect. 
 
 The moth at first is rather sluggish, and can be easily captured. After 
 it has been abroad for some days it is wild and more or less muti- 
 lated. This Cossus is not attracted by sugar, as might be expected 
 from its aborted tongue.* The moth seems to belong to the genus Cos- 
 sus Fabr., and not to be congeneric with Xystus robiniw. The head is 
 short, eyes naked, labial palpi small, appressed, scaled. The thorax is 
 thickly scaled, the scales gathered into a ridge behind, and is squarer 
 
 * The writer is desirous of producing all the known facts in reference to this insect 
 in th ; s paper; therefore the descriptive parts which have heen published before are 
 reproduced. 
 
 (49) 
 5135 4 
 
50 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 in front than in Xystus, not so elongate or so elevated dorsally. The 
 male antennae are bipectinate ; the lamellae rather short and ciliate. 
 The female antennae are serrated. It is allied to the European Cossus 
 terebra F., but is a larger insect. It differs from G. qaerciperda Fitch 
 by the absence of any yellow on the male hind wing, and by its darker 
 color and closer reticulations. 
 
 In color this species is black and gray. The edges of the thorax and 
 collar are shaded with gray, more noticeable on some specimens than 
 others. The primaries are covered with black reticulations, which are 
 not always identical in their minor details in different specimens, nor 
 sometimes on both wings in the same specimen. Beyond the cell there 
 is a transverse continuous line, broader than the rest, and outwardly 
 bent over median nervules. The brown color is blackish over nearly 
 two-thirds of the primaries from the base, and outwardly gray ; hind 
 wings rounded in both sexes, with blackish hairs at base, pale and sub- 
 pellucid, with short gray fringe, before which there is a narrow black- 
 ish, edging. The abdomen is blackish. The males are smaller than the 
 females. The smallest male expands about 40 mm , the largest female 
 over 60 min (see Plate I, Figs. 10, 11, and 12). While thus far the Centre 
 (N. Y.) locality has proved to be the chief home of this Cossus, it will 
 undoubtedly be found elsewhere wherever the Populus tremuloides 
 is found. Several pupa-cases of this species have been found in the 
 corporate limits of Albany. Usually trees of less than 1 foot in diameter 
 are attacked, although in one instance a pupa-case was found in a tree 
 measuring 16 inches in diameter. 
 
 It is a very different matter to observe the changes of insect life from 
 the eggs to the imago when feeding upon the foliage of vegetation than 
 where the larvae have bored deep into a tree trunk and feed upon the 
 ligneous fiber and its circulating fluids. To obtain this information it 
 has been necessary several times each year to cut down trees bearing in- 
 dications of its ravages, and to dissect them into fragments the size of 
 kindling-wood. The months of October, April, and June were selected 
 as suitable times for such investigations. October 14 we visited a tree 
 for the purpose of obtaining caterpillars, and from a limb 4 feet in length 
 six caterpillars were taken, two of which were occupying cells as seen in 
 the engraving. 
 
 April 2 we cut from a tree a limb 3 feet in length, and in it we found 
 seventeen caterpillars of three distinct sizes, indicating a growth for each 
 year. The larger ones were not fully grown. All of them were actively 
 passing through their tunnels in the wet wood, through which the sap 
 was freely flowing. Not any of the caterpillars were occupying pupa- 
 cells at this time. June 12, 1881, we again visited a tree when the insects 
 were emerging. The tree selected was far advanced in decay, from the 
 effects of the tunneling of the larvae ; only about 4 feet of the trunk was 
 alive, with a few lateral branches in foliage, scarcely enough to support 
 its respiration. In the trunk were found fresh pupa-cases, pupae, and 
 
OY THE NORTH AMERICAN COSSID^E. 51 
 
 caterpillars. Again three crops of larvae were found ; the larger ones 
 were inactive and lying in the sap-wood, with their heads close to the 
 bark which was gnawed nearly through to the outer surface. These 
 caterpillars had evidently taken their last position preparatory to their 
 final transformation into pupae. Pupae were also found occupying the 
 same position, and when the bark was removed were visible. 
 
 The larva taken October 14 from its burrows is 45 mm in length, of a pale 
 flesh color. It is a little broader anteriorly. The pro thoracic segment 
 is blackish brown above, the dark color edged with a dirty orange shad- 
 ing. The head is mahogany brown, shining, slightly roughened. The 
 mandibles are black, with strong teeth. The surface of the head gives 
 rise here and there to single scattered hairs. The antennae are three- 
 jointed; the second joint gives rise to a single long hair. The seventh 
 eighth, ninth, and tenth abdominal segments are provided with false 
 feet. The segments are marked with a lateral row of brown dots above 
 the reddish stigmata, and there is a row of similar dots, two to a segment r 
 on each side of the dorsal line. These dots give rise to single pale hairs- 
 The larva moves with freedom either backward or forward. The bur 
 rows which it excavates are about 15 mm in width and terminate in the 
 pupating cell, which is about 40 ,um in length, smooth ; the extremity 
 towards the opening is closed by a wad of finer and then coarser filings 
 of the wood. The coarser splinters are not detached entirely from the 
 wood, but are split up by the larvae all around the top of the cell, and 
 project like bristles, appearing somewhat as those wooden toy trees which 
 are made for children, and which are formed by shaving down the wood 
 and leaving the shavings adhering by one end. These splinters make 
 a firm wad. Against them are piled a quantity of finer chips or thin 
 filings, which are loose but pressed together. 
 
 The cell (Plate 1, Fig. 7) is about 40 mra from the outer bark of th<> tree, 
 and the chrysalis (Tigs. 8 and 9) makes its way to the air through the 
 burrow, by means of its teeth on the segments and the spinose process; 
 on the front, by which it forces itself, by stretching and contracting the 
 abdomen, through the wood scrapings which close the cell, until it comes 
 to the end. We have noticed a fine thread of silk proceeding from the 
 spinneret of the larva, although in the cocoon we have found no silk 
 whatever. The cocoon or pupa-cell seems to have been formed by wedg- 
 ing first coarser and then finer strips of the wood together, and seems 
 to be merely a more carefully and smoothly finished enlargement of the 
 original burrow. 
 
 A specimen of the pupa which I have examined is about 30 mm in length, 
 narrow, brownish black, shining rugose. The clypeus presents a strong, 
 broad, spinous process, supported at base by lateral projections. On? 
 the under side it descends into a wide sulcation terminating in a broad 
 projection. The capital appendages are visible, and here and there arise 
 isolated hairs as in the previous stage. The abdominal segments are 
 provided with teeth over the dorsum, decreasing in size to the stigmatal 
 
52 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 line. The anal segment is provided with two unequal-sized terminal 
 teeth on each side of the vent. (Plate J, Figs. 8 and 9.) 
 
 The chrysalides vary much in size, and some of them are infested with 
 an ichneumon fly, which preys on the caterpillar. A pupa was observed 
 endeavoring to make its way to the surface of the bark, but seemingly 
 unable to extricate itself, when assistance was rendered by enlarging 
 the orifice. It was laid in a paper box for hatching. A few days after- 
 wards many minute ichneumons were observed resting upon the wall 
 near the box. On examination they were found to be escaping through 
 minute holes in the pupa, which would barely admit a No. 3 entomolog- 
 ical pin. Fifteen of these perforations were counted in this pupa. I 
 presume that the larva of the Oossus is pursued in its burrows by the 
 parent parasite. If so it is curious that the Cossus pupa is not killed 
 by the parasites until it has worked itself up to the mouth of the tun. 
 nel, thus allowing the ichneumon flies to escape outside. 
 
 When ready to emerge, the pupa, by means of stout cusps on its ab- 
 dominal segments, works itself to the end of the opening, and with its 
 pointed head-case the thin portion of bark which has been left by the 
 caterpillar's instinct is severed and removed. It pushes itself through 
 the opening as far as the base of the abdomen, by a sort of rotary mo- 
 tion, which acts in its mode of cutting like a carpenter's center-bit. The 
 thoracic end of the pupa after exposure a short time to the air becomes 
 dry and splits, and the moth escapes, climbing up the bark of the tree, 
 shaking out its wings, until developed. After the moth has escaped the 
 empty pupa-case may still be seen protruding from the entrance of the 
 tunnel. It is not true that Cossus centerensis prefers dead wood to bur- 
 row in. It is a fact that it is most frequently found in partially decayed 
 trees, for after the larvae obtain a lodgment by its perforations in di- 
 verse directions through the heart and alburnum, admitting air and 
 water, it causes irreparable decay. There are three species of poplar 
 found in the vicinity of Centre,* viz, grandidentata, dilatola, and tremu- 
 loides, but as yet C. centerensis has only been found in the Populus 
 tremuloides. 
 
 It is stated by Harris that C. ligniperda deposits her eggs on the bark 
 near the root of the tree, which I believe is the habit of most of the 
 borers. It would seem from the following that it is not the invariable 
 mode. In splitting open a tree trunk on June 12 a Oossus was observed 
 to fly from the cleft, which on being captured proved to be a female. 
 It was supposed she had taken possession of a tunnel for the purpose 
 depositing her eggs. The loose debris from the excavations w r as 
 gathered together, an examination of which revealed Oossus eggs. 
 (Plate I, Figs 1 and 2.) The female was confined in a box; the next 
 morning she had deposited fifty-two eggs ; some of them were attached 
 to the sides and others on the bottom of the box. Some of the eggs 
 
 Now called Karuer. 
 
OX THK NORTH AMERICAN COSSIDJE. 53 
 
 were deposited singly and some in confused heaps, and were attached 
 to each other and to the box with a viscid substance. 
 
 Another female was captured June 20, and in forty-eight hours after 
 being pinned she had deposited sixty eggs, which varied somewhat in 
 color from the former. 
 
 The Cossns after being pinned is very restive, especially while de- 
 positing her ova and by the constant motion of the oviposter in endeav- 
 oring to extrude the ova. The loo-e abdominal scales are removed and 
 attached to the eggs by the moist viscid fluid with which they are cov- 
 ered, and which often gives them the appearance of being clothed with 
 scales. A few of the ova collected this season have this appearance, 
 but a strong lens exposes the true condition. C. centerensis is not so 
 prolific as some of the other species of Cossidce. C. robinice Peck and 
 C. querciperda Fitch have been known to extrude upwards of three 
 hundred ova. In European species over one thousand ova have been 
 found on dissection. The ruin of whole forests of timber in which these 
 insects revel is doubtless prevented by the destruction of the eggs by 
 ants and birds, the size of the eggs being sufficient to form a tempting 
 morsel. In a state of nature the female Oossus deposits a small num- 
 ber of her ova upon each tree which she visits until her supply is ex- 
 hausted. 
 
 This season the enlarged perforations through the bark show- unmis- 
 takable evidence that the trees had been recently visited by wood- 
 peckers, which could find little difficulty in procuring an abundance of 
 full-grown larvae. 
 
 C. centerensis is found throughout the region known as the pine bar- 
 rens, which cover an area of perhaps 12 square miles between Albany 
 and Schenectady. The soil of this region seems especially well adapted 
 to the growth of the timber which it supports. 
 
 At the present time no correct observations have been made in ref- 
 erence to the molts'of the caterpillars, but information on this subject. 
 will soon be obtained from Mr. A. H. Mundt, of Illinois, who has had 
 opportunities of observing, up to the fourth molt, the caterpillars of 
 C.robiniw, which are found in the willows and poplars in his vicinity. 
 
 Cossns centerensis appears every year, and from observations and from 
 numerous examinations of the trees by actual sections during the three 
 months of the year enumerated, I am convinced that the caterpillars 
 are not fully matured until the end of the third year, when they arrive 
 at their perfect or winged state. The pupa state is comparatively 
 short, lasting less than a month before the moth appears. From figures 
 3, 4, and 5 of Plate I we see representations of caterpillars found Octo- 
 ber 14, which establish the fact beyond dispute, through observations 
 extending over many years, that it requires three full years for the cat- 
 erpillar to arrive at maturity. 
 
54 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 Oossus angeezi Bailey. 
 
 (Plate II, Fig. 6.) 
 
 We repeat the original description of this species, given in Papilio for 
 June, 1882 (Vol. II, No. 6, p. 93) : 
 
 Cossus angrezi. ii. 8. $ . Head somewhat narrow oil the vertex. Collar and head 
 yellowish gray, thorax black ; the edges of the tegulse shaded with yellowish gray. 
 Fore wings with a nearly white ground, shaded with black, and with black reticula- 
 tions. Hind wings yellowish gray, mottled with blackish outwardly. The fore wings 
 have the costal edge pale, marked with black ; the black shading obtains on costa at 
 apical third, and over the whole wing at terminal third, extending obliquely down- 
 "wards-and inwards,* there are a series of interspacial longitudinal black streaks be- 
 fore the margin, more or less denned. Fringes whitish, dotted with black opposite 
 iihe ends of the veins, which latter conversely are whitish. Thorax shaded with yel- 
 lowish gray behind. Abdomen dark gray. Beneath the wings repeat the markings 
 w<ery distinctly, owing to the strong contrast of the pale ground color with the black 
 markings. Expanse, 82 mm . 1 9. Wells, Elko Co., Nevada. From the late Mrs. 
 •Caroline Chase. Type, coll. James S. Bailey. 
 
 This I believe is a true Cossus, although the 8 is not known to me. 
 The shape of the wing' is as in center ensis. The structure is that of 
 -Cossus, and not of Prionoxystus. The thorax is subquadrate, the vest- 
 iture short and thick. The interspacial black dashes along the prima- 
 ries subterminally distinguish it specifically. The pre-apical transverse 
 black streak or line resembles that of C. centerensis. The hind wings 
 .are faintly reticulated. The ground color is a yellowish white. The 
 biack blotches on fore wings of robinice are here wanting, while there is 
 a diffuse discal shade blotch, another above and beyond it on costa, and 
 the wing shows a wide, soft, blackish shading, obliquely edged inwardly 
 sand covering the outer portions of the wing. Except the antennae my 
 type is perfect. Beneath it is strongly marked, and reminds one of 
 €>. robinuv Peck, but the shape of the wing is not like that species. 
 The thorax is black above, not gray with black stripe on tegulse, and 
 the collar is discolorous, pale yellowish gray. This species ought to be 
 recognizable. The shape of the thorax is like Cossus, as is the vestiture, 
 so that I am not prepared to find that the male has the peculiarities of 
 €. robiniw and querciperda Fitch. I hope Western collectors will solve 
 the question. But I cannot regard angrezi as having anything to do 
 with the question of a Western representative of robinke. From Her- 
 rieh Schaefer's figure, and what has been published, I believe that robi- 
 niw is found across the continent. 
 
 Prionoxystus robini^e Peck. 
 
 I have a female with extended ovipositor. We have probably only 
 one species, reaching from California to the East, and this is phy tophagic, 
 feeding on the oak, willow, as well as the locust and other trees. No 
 difference by which these forms can be separated is appreciable. The 
 female is redescribed as crepara by Dr. Harris. The insect was common 
 in 1882 in different localities in New York State. 
 
ON THE NORTH AMERICAN COSSiD^. 55 
 
 Structure. — The female antennae are pectinate. The terminal seg- 
 ment of the abdomen narrows and becomes elongated and cylindrical 
 towards its extremity. The male secondaries are half the size of the 
 female's and obliquely and sqarely cut off along external margin, being 
 also discolorons and of a bright yellow. The thorax is long and 
 narrowed, elevated in front of the fore wings. The head is longer 
 and more projected compared with Cossus, the prothorax narrowing 
 anteriorly, neck-like. The labial palpi are longer and more distinct. 
 The fore wing is more produced apically, longer and narrower ; the outer 
 edge less full and more oblique. The vestiture is sparse, thin, flatly 
 laid on in body and wings. The hard chitinous tegument is less 
 hidden, and the whole insect has a certain coleopterous aspect, remind- 
 ing us of the wood-boring Gerambyeidce, such as Prionus, quite strongly. 
 The aspect is not moth-like, but hard and chitinous. Just as there is a 
 certain resemblance between different species feeding on a particular 
 plant, as the pine-feeders, so do all borers have some points in common. 
 The generic characteristics all hold good with the second species of this 
 genus. 
 
 Prionoxystus querciperda Fitch. 
 
 (Plate II, Fig. 4.) 
 
 This species is smaller than robinice, the $ expanding 46 or 47 mm , the S 
 about .10 mm less. The male hind wings seem translucent, but on hold- 
 iug them obliquely in certain lights the yellow tint may be seen plainly. 
 This smaller and rarer species occurs also in Texas. It is freer from 
 reticulations and more transparent than any other form. 
 
 We have representatives of four genera of Gossidw in the United 
 States, viz., Hypopta, Gossas, Prionoxystus, and Gossula. As to the species 
 described under Cossus, several are incompletely described, and none 
 are now so well known as G. centeremis, which has been studied by my 
 son, Dr. Theodore P. Bailey, and myself. 
 
 « Cossula magnjfica Bailey. 
 
 (Plate II, Figs. 1, 2, and 3.) 
 
 [This species was described by Dr. Bailey in Papilio for July, 1S82 
 (Vol. II, No. 6, p. 94), with notes upon its habits. The larva bores into 
 live-oak (Qtiercns virens) in Florida. No new matter was prepared on 
 this species at the time of his death, and we do not consider it necessary 
 to repeat the original description. — C. V. B.l 
 
REPORT ON THE EXAMINATION OF RAW SILKS. 
 
 By 
 
 William McMurtrie, e. m., ph. d. 
 
 Professor of Chemistry in Illinois Industrial University. 
 
 Champaign, III., February 8, 1883. 
 Sir : I have just completed the examination of the samples of silk 
 you offered for measurements of fineness and tensile strength of the 
 fibre, and I take pleasure in submitting herewith the results we have 
 been able to obtain, together with a brief description of the methods 
 employed in the examination, and some considerations of the relations* 
 exhibited in the results. 
 Yery respectfully, 
 
 Wm. McMurtrie. 
 
 Prof. 0. Y. Eiley, 
 
 U. 8. Entomologist. 
 
 EEPORT. 
 
 Description of the material. — The material furnished for the examina- 
 tion about to be described consists of eight samples of cocoons of vari- 
 ous races of silkworms, grown in this country in different localities, with 
 different kinds of food. Each sample was inclosed in a box bearing an 
 inscription by which the sample was distinguished, and the latter is to 
 be found in Table I at the bottom of the column, giving the results of the 
 measurements of the fineness of the respective samples. No measure- 
 ments were made to determine the size of the cocoons or the weight of 
 the silk they are capable of yielding, for the latter would involve the 
 use of appliances not at our disposition. But it may be saic^that they 
 were of good size, perfectly firm and uniform, clean and of good color \ 
 in fact, from all appearances, evidently of excellent quality. This con- 
 stitutes all the information we have concerning the history of the co- 
 coons. 
 
 Object of the examination. — The examination, as requested, was more to 
 determine the quality of silk grown in the United States as compared 
 with that obtained in European culture. For the purposes of the com- 
 parison we must refer to the published works giving the fineness and 
 strength of the European raw silks, since we have had no material with 
 which to determine the necessary data. From the appearance of the 
 cocoons, however, there can be little doubt that the comparison will 
 prove favorable to the American product. 
 
 (56) 
 
THE MICROSCOPIC EXAMINATION OF SILK FIBRES. 57 
 
 Preparation of the material for examination. — As has already been in. 
 timated, we were provided with no special apparatus for reeling the silk 
 from the cocoons, and specimens for the measurement of the fineness 
 and one set for determination of the tensile strength were obtained by 
 simply cutting open the cocoons, separating the layers by pulling them 
 apart, and taking portions of fibre at random from each part. Xo at- 
 tempt was made to determine in this examination differences in the 
 quality of the fibre dependent upon the location of the part in the strati- 
 fication of the cocoon, and hence the period of the spinning operation at 
 which it was formed, both because the time at our disposal for making 
 the examination had been limited and because this did not constitute 
 a principal object in the examination desired. There is no doubt, how- 
 ever, that an investigation with this regard would furnish results of 
 great interest and value. 
 
 The fibres separated in this way were designated as " dry ; " that is, no 
 moisture was employed in their separation. Jt is well known that the 
 strength of the cocoon depends upon the glutinous character of the fibre' 
 on the instant of its issue from the spinnerets of the insect, and that the 
 glutinous matter covering the fibre and forming a portion of its constit- 
 uent structure readily softens in warm water. And it is further well 
 known that this principle is applied practically in the industrial pro- 
 cesses of silk reeling. To determine what influence this may have upon 
 the fibre, we submitted a series of the cocoons to the action of warm 
 water, and when they were sufficiently softened secured the end of the 
 fibre and wound it upon slips of card-board, thus applying in a crude 
 way the process of reeling. The fibre so obtained has therefore been 
 designated as " wet." The influence of the treatment to which the fibre 
 is subject in this process of separating it will be discussed later on, and 
 is manifest in the results given in Table II. 
 
 Measurements of fineness. — If the fibre of raw silk be examined with a 
 microscope of sufficiently high power, it appears to consist of a more 
 or less flattened strip, somewhat depressed through the middle, so that 
 its cross-section may be likened to the longitudinal section of a dumb- 
 bell (co), as shown in the figure. This is explained by the fact that the 
 fibre in the glutinous condition is discharged by the worm in spinning, 
 from the spinnerets located on the underside of the head, near the man- 
 dibles. As they pass out and are stretched by the worm in its to-and- 
 fro motions in spinning, the two fibres are cemented together more or 
 less firmly according to the rapidity of spinning. 
 
 Sometimes these primary fibres, as they may be termed, are separate 
 and free from each other, and each is an almost perfect elongated cylin- 
 der. But in most cases they are firmly joined, and the two form a 
 compact whole, constituting the raw fibre of the cocoon. It is plain, 
 therefore, that this raw fibre is not cylindrical but ribbon-shaped, and 
 that it has two lateral axes of different lengths, so that on some accounts 
 a single measurement of a fibre does not represent its fineness, while at 
 
58 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 the same time there is danger that in taking the measurements with the 
 microscope the longer axis of the fibre maybe taken in some cases, while 
 in others the shorter axis may be inadvertently chosen. So also it 
 may to some appear extremely desirable that in order to fairly deter- 
 mine the fineness of the fibre both axes should be measured, and there 
 is much of reason in this opinion. On the other hand, if we bear in mind 
 that the breadth of the ribbon will depend upon the diameter of the in- 
 dividual fibres constituting the raw fibre, it will be seen that the breadth 
 of the fibre, or its longer lateral axis, may be accepted as a fair repre- 
 sentation of the degree of fineness of this condition of the staple. 
 
 The method of taking the measurements of fineness is therefore as fol- 
 lows : The cocoon is cut open and separated into the different layers of 
 which it is made up. A small tuft of fibres is then cut from each, taken 
 at random. These are then cut to suitable length and mounted upon the 
 glass object slide for microscope, immersed in Canada balsam, and covered 
 with a thin glass circle. When the cover is in place the slide is gently 
 warmed and laid aside for the balsam to dry and harden. When ready 
 for the purpose each slide is placed upon the stage of the microscope, 
 the fibres successively brought into focus, and the width of the image at 
 its widest part measured by means of an eye-piece micrometer, which 
 has been standardized by means of a stage micrometer graduated to centi- 
 millimeters. The relative measurement taken in this way is reduced to 
 the absolute standard and the result entered in the record. The object 
 of taking the width of the image at its widest part is to obviate the 
 danger of measuring the image of the fibre turned more or less with 
 its edge toward the eye, a difficulty that would materially vitiate the 
 result. 
 
 In experiments made in this connection, as well as in the measure- 
 ments of wools and cottons in a similar way, it has been found both ad- 
 visable and necessary, in order to arrive at satisfactory conclusions con- 
 cerning the property under consideration, to make measurements of at 
 least thirty fibres in each sample. For purposes of comparison every 
 measurement is entered upon the record, which is given in the following 
 table: 
 
THE MICROSCOPIC EXAMINATION OF SILK FIBRES. 
 Table I. — Measurements of the fineness of raw silk. 
 
 59 
 
 Catalogue number of sam- 
 
 I. 
 
 
 II. 
 
 
 III. 
 
 
 ples. 
 
 
 
 
 
 
 
 1 
 
 
 3.00 
 
 2. 50 
 3.50 
 
 3. 7.") 
 2.875 
 3.75 
 3. 75 
 3.875 
 3.50 
 2. 625 
 
 2. 875 
 3.00 
 
 3. 50 
 2.50 
 3. 50 
 
 
 2. 625 
 
 3. 50 
 
 4. 625 
 2. 50 
 2. 625 
 2.50 
 2.875 
 3.875 
 3.25 
 2.75 
 2.75 
 2.625 
 3.00 
 3.00 
 3.25 
 
 
 3.25 
 
 2. 625 
 
 2.75 
 
 2. 875 
 
 2.75 
 
 3.50 
 
 2.75 
 
 3.25 
 
 2.75 
 
 3.25 
 
 2. 50 
 3.00 
 3.00 
 
 3. 00 
 3. 00 
 
 
 
 
 2. 375 
 
 
 3.00 
 
 2. 625 
 
 
 
 
 3.75 
 
 
 2.25 
 
 2.50 
 
 
 
 
 2.75 
 
 
 2. 625 
 
 
 2.375 
 
 
 
 
 3.00 
 
 
 2.875 
 
 
 2. 625 
 
 . 
 
 
 
 2.50 
 
 
 2.25 
 
 
 2. 50 
 
 
 
 
 3.125 
 
 
 2.75 
 
 
 2.50 
 
 
 
 
 3. 25 
 
 
 3.00 
 
 
 2.75 
 
 
 
 
 2.50 
 
 
 2.75 
 
 2.75 
 
 
 
 
 3.125 
 
 
 2. 625 
 
 2.50 
 
 
 Actual measurements in } 
 
 
 2.625 
 
 
 2. 875 
 
 
 3.00 
 
 
 ceutimillimeters. ] 
 
 
 3.375 
 2. 875 
 
 
 3.00 
 2.50 
 
 
 2.125 
 2.375 
 
 
 
 
 3.50 
 
 
 2.75 
 
 3.00 
 
 
 
 
 2.375 
 
 
 2.50 
 
 2.75 
 
 
 
 
 3.50 
 
 
 2.75 
 
 2. 625 
 
 
 
 
 2. 75 
 
 
 2.50 
 
 2.875 
 
 
 
 
 2.75 
 
 
 3.00 
 
 2. 125 
 
 
 
 
 3.2.i 
 
 
 2.875 
 
 3.00 
 
 
 
 
 2. 6LT) 
 
 
 3.00 
 
 2.75 
 
 
 
 
 3.00 
 
 
 2. 875 
 
 2. 50 
 
 
 
 
 2. 625 
 
 
 2.75 
 
 2. 50 
 
 
 
 
 3 12.-) 
 
 
 2.625 
 
 2.50 
 
 
 
 
 2. 75 
 
 
 2.75 
 
 3.00 
 
 
 
 
 2. 875 
 
 
 2. 375 
 
 2.25 
 
 
 
 
 3.00 
 
 
 3. 125 
 
 2.75 
 
 
 
 
 2.00 
 
 
 3.25 
 
 3.25 
 
 
 
 
 3. 375 
 
 
 2. 25 
 
 2.875 
 
 
 
 
 3. 25 
 
 
 3. 375 
 
 3.25 
 
 
 
 
 3.50 
 
 
 2. 625 
 
 2.75 
 
 
 
 
 2.50 
 
 
 3. 25 
 
 
 3.00 
 
 
 
 
 2. 75 
 
 
 2. 75 
 
 
 2.50 
 
 
 
 
 3.00 
 
 
 2.75 
 
 
 3.00 
 
 
 
 
 3.25 
 
 
 3. 25 
 
 
 2 50 
 
 
 
 
 3.00 
 
 
 3.25 
 
 
 2.50 
 
 
 I 
 
 
 2.25 
 
 
 3.00 
 
 
 2.75 
 
 
 A verage 
 
 
 3. 015 
 
 
 2.878 
 
 
 2.748 
 
 
 
 
 s 
 
 (0 
 
 .a 
 
 o 
 
 a 
 
 09 
 
 5H 
 
 O 
 
 a 
 
 92 
 
 
 
 • 
 
 3 
 
 a © 
 
 BJ 
 
 
 a *« 
 
 g4 
 
 
 a^ 
 
 n£ 
 
 
 S ? 
 
 +3 <s 
 
 3 a 
 
 
 
 es a 
 5 a 
 
 l§ 
 
 a' ?° 
 
 •43 3 
 
 3 a 
 
 5 fl 
 
 £ a 
 " rt 
 
 
 o 
 
 ■§.* 
 
 ♦""S 
 
 S3 
 
 53 
 
 J- 
 
 
 
 $% 
 
 a *-■ 
 
 O) 
 
 
 
 
 « a 
 
 
 a 
 
 3 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 
 H 
 
 H 
 
 1— 1 
 
 H 
 
 H 
 
 M M 
 
 
 H 
 
 Recapitulation : 
 
 
 
 
 
 
 
 
 
 
 Highest 
 
 3.875 
 
 1. 5255 
 
 1_ 
 
 4. 625 
 
 1. 8208 
 
 1 
 
 3. 50 
 
 1. 3779 
 
 T*B 
 
 Lowest 
 
 9 no 
 
 0. 7874 
 
 65S 
 
 2! 25 
 2. 878 
 
 0. 0858 
 
 549 
 
 2! 125 
 
 2.748 
 
 0. 8366 
 
 Average 3.015 
 
 1. 1870 
 
 T-269 
 842 
 
 l! 1330 
 
 Tl2§ 
 1»2 
 
 1.0818 
 
 ssi- 
 
 Number of measurements 
 
 
 
 
 
 
 
 
 above average 
 
 
 21 
 
 
 19 
 
 
 30 
 
 
 
 
 Number of measurements 
 
 
 
 
 
 
 
 
 below average 
 
 
 29 
 
 
 31 
 
 
 20 
 
 
 
 
 
 | Yellow 
 
 Japan eg 
 berry. 
 
 e; mul- 
 
 Yellow 
 a 
 
 Japane 
 ^e orang 
 
 se; Os- 
 
 9. 
 
 Riley's 
 ne'se ; 
 11 ye 
 
 yellow 
 Osage 
 ars. 
 
 Jap a- 
 orange ; 
 
60 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 Table I. — Measurements of tl\e fineness of raw silk — CoutiDued. 
 
 Catalogue number of sam- 
 
 IV. 
 
 
 V. 
 
 
 
 V. 
 
 
 ples. 
 
 
 Tellow. 
 
 
 
 White. 
 
 
 r 
 
 i 
 i 
 
 2.375 
 
 2.50 
 
 2.00 
 
 2.75 
 
 2.00 
 
 2.50 
 
 - 2.75 
 2.50 
 
 > 2.50 
 2.25 
 2.75 
 2.875 
 2.625 
 2. 125 
 2.375 
 2.75 
 3.00 
 2. 375 
 2.75 
 2.25 
 2.75 
 2.75 
 2.50 
 2.75 
 
 
 
 2.125 
 
 2.50 
 
 2.50 
 
 2.50 
 
 2.375 
 
 2.25 
 
 2.375 
 
 2.50 
 
 2.25 
 
 2.50 
 
 2.50 
 
 2.25 
 
 1. 875 
 2.125 
 2.75 
 2.50 
 2.50 
 2.00 
 2.75 
 2.L5 
 2.875 
 2.50 
 
 2. 375 
 2.50 
 
 
 
 2.00 
 
 2.50 
 
 3.00 
 
 2.75 
 
 2. 625 
 
 2.25 
 
 2.50 
 
 2. 25 
 
 3.00 
 
 2.50 
 
 2.50 
 
 3.00 
 
 2.25 
 
 2.375 
 
 2.00 
 
 2.50 
 
 2.00 
 
 2.50 
 
 2.50 
 
 2.25 
 
 2.50 
 
 2. 125 
 
 3.00 
 
 3.25 
 
 
 Actual measurements in 
 
 2.25 
 
 
 
 2.25 
 
 
 
 2. 375 
 
 
 centimillimeters. 
 
 2.125 
 
 2. 625 
 
 2.75 
 
 2.375 
 
 2. 625 
 
 2.50 
 
 2.75 
 
 2. 625 
 
 2.75 
 
 2.50 
 
 2.375 
 
 2.50 
 
 2.50 
 
 2.25 
 
 3.25 
 
 2. 625 
 
 2.00 
 
 2.50 
 
 2. 125 
 
 2. 625 
 
 2.50 
 
 2.75 
 
 2.375 
 
 2.50 
 
 2.375 
 
 • 
 
 
 2.50 
 
 2.50 
 
 2.375 
 
 2.50 
 
 2 75 
 
 2. 50 
 
 3.25 
 
 3.00 
 
 1.875 
 
 1.75 
 
 2.75 
 
 2. 375 
 
 2.75 
 
 2. 625 
 
 2. 375 
 
 2.50 
 
 2.75 
 
 2.25 
 
 3.00 
 
 2.75 
 
 2. 625 
 
 2.50 
 
 2.00 
 
 2.25 
 
 2.875 
 
 
 
 2.75 
 
 2.50 
 
 3.00 
 
 2.25 
 
 2.50 
 
 2.50 
 
 2.125 
 
 2. 125 
 
 1. 875 
 
 2. 75 
 2.25 
 2.5i 
 2.75 
 2.3:5 
 2.25 
 2.50 
 
 3. 25 
 
 2. 75 
 3. 125 
 
 3. 00 
 2.25 
 2. 25 
 2.75 
 3.00 
 2.50 
 
 
 Average 
 
 2.513 
 
 2.465 
 
 
 2.528 
 
 
 
 
 
 i> 
 
 a 
 
 to 
 
 5*H 
 O 
 
 & 
 
 5 
 
 c 
 
 i 
 
 S 
 
 J- 
 
 c 
 
 
 
 T3.C 
 
 <» . 
 
 
 'C-^ 
 
 oc . 
 
 
 ■nS-c 
 
 w . 
 
 
 
 
 ^rP 
 
 
 c 2 
 
 
 
 2 
 
 
 
 e g 
 
 a a 
 
 2~ 
 
 -3 A 
 
 S g 
 
 CO A 
 33 .1-1 
 
 Co 
 
 .§2 
 
 e« PI 
 
 C a 
 
 
 
 53 
 
 O-IH 
 
 TO pj 
 
 
 5 c 
 
 
 13* 
 
 2. * 
 
 « Pt 
 
 
 
 $% 
 
 <M « 
 
 
 £<* 
 
 45 e8 
 
 O 
 
 ^c 
 
 «H K 
 
 
 a 
 
 c 
 
 P 
 
 a 
 
 a 
 
 e) 
 
 1=1 
 
 pi 
 
 PI 
 
 
 M 
 
 
 M 
 
 
 H 
 
 
 H 
 
 H 
 
 H 
 
 Recapitulation : 
 
 Highest- 
 
 
 
 
 
 
 
 
 
 
 3.25 
 
 1. 2735 
 
 1 
 
 3.25 
 
 1. 2735 
 
 i 
 
 3.25 
 
 1 . 2735 
 
 1 
 
 Lowest 
 
 2.00 
 
 0. 7874 
 
 TtfTo 
 
 1.75 
 
 0. 6889 
 
 i 
 
 T55T 
 
 1.875 
 
 0. 7380 
 
 - 1 -* 
 
 
 2.513 
 
 ' 0. 9893 
 
 2.465 
 
 0. 9704 
 
 2.528 
 
 0. 9952 
 
 T(5D4 
 
 
 Number of measurements 
 
 
 
 
 
 
 
 
 
 above average 
 
 21 
 
 
 
 30 
 
 
 
 17 
 
 
 Number of measurements 
 
 
 
 
 
 
 
 
 
 
 29 
 
 
 
 20 
 
 
 
 33 
 
 
 
 
 
 Riley's white 
 nese ; Osage < 
 
 Japa- 
 
 
 h's blac 
 
 k Thi- 
 
 Fasnac 
 
 h's bla 
 
 sk Thi- 
 
 
 )range ; 
 
 
 bet. 
 
 
 
 bet. 
 
 
 
 11 j ears. 
 
 
 
 
 
 
 
 
MEASUREMENTS OF THE FINENESS OF RAW SILK. 
 Table I. — Measurements of the fineness of raw silk— Continued. 
 
 61 
 
 Catalogue number of sam- 
 ples. 
 
 VI. 
 
 VII. 
 
 
 
 VIII. 
 
 
 r 
 
 
 2.50 
 
 2.50 
 
 3.125 
 
 2.00 
 
 3. 125 
 
 3.00 
 
 3.00 
 
 2.75 
 
 2. 125 
 
 2.75 
 
 2.125 
 
 3.50 
 
 2.75 
 
 2.25 
 
 2. 875 
 
 3.00 
 
 2.25 
 
 3.00 
 
 2.75 
 
 2.375 
 
 2. 50 
 
 3. '25 
 
 
 
 
 3.50 
 
 2.75 
 
 3.00 
 
 3.00 
 
 3.25 
 
 2.625 
 
 2.50 
 
 3.00 
 
 3.00 
 
 3.25 
 
 3.50 
 
 3.375 
 
 2.50 
 
 2. 875 
 2.75 
 
 3. 50 
 3.00 
 3. 25 
 
 2. 50 
 2.75 
 
 3. 50 
 3.50 
 
 
 
 
 
 2.75 
 
 2.00 
 
 2.00 
 
 2.50 
 
 2.50 
 
 3.00 
 
 2 50 
 
 2. 625 
 
 2 375 
 
 2.50 
 
 2.375 
 
 3.50 
 
 2.00 
 
 2.50 
 
 2.50 
 
 2.25 
 
 2. 625 
 
 2. 375 
 
 2.75 
 
 2.50 
 
 2.00 
 
 2.50 
 
 
 
 
 3.375 
 
 
 
 
 3.00 
 
 
 
 
 2. 50 
 
 
 
 
 2.50 
 
 
 
 
 3.25 
 
 
 
 
 2. 25 
 
 
 Actual measurements in , 
 
 
 3.00 
 
 
 
 
 2. 875 
 
 
 
 
 2.25 
 
 
 centimillimeters. 
 
 
 3.00 
 2. G25 
 
 2. 75 
 3.50 
 2.875 
 
 3. 25 
 2.875 
 2 50 
 2.50 
 2.875 
 3.25 
 2.75 
 
 
 
 » 
 
 3 25 
 
 3.00 
 
 3.00 
 
 2.875 
 
 3.00 
 
 2. 75 
 
 2. 875 
 
 2. 75 
 
 4.25 
 
 3.25 
 
 2. 50 
 
 3. 125 
 
 
 
 
 2. 50 
 
 2.50 
 
 2.75 
 
 2. 375 
 
 2.50 
 
 2.50 
 
 2.00 
 
 3.00 
 
 2.25 
 
 2.00 
 
 3.25 
 
 2. 25 
 
 
 
 
 3.50 
 
 
 
 2. 75 
 
 
 
 
 2.25 
 
 
 
 
 2.875 
 
 
 
 
 2.25 
 
 
 
 
 2.75 
 
 
 
 
 3. 25 
 
 
 
 
 2.75 
 
 
 
 
 2. 50 
 
 
 
 
 3.50 
 
 
 
 
 3.50 
 
 
 
 
 2. 25 
 
 
 
 
 3.00 
 
 
 
 
 3.25 
 
 
 
 
 2. 625 
 
 
 
 
 3.50 
 
 
 
 
 3. 00 
 
 
 
 
 2.75 
 
 
 
 
 3.00 
 
 
 
 
 2. 75 
 
 
 
 
 3.00 
 
 
 
 
 3.00 
 
 
 
 
 3.00 
 
 
 
 
 2. 25 
 
 
 
 
 2.50 
 
 
 
 
 3. 50 
 
 
 
 
 2. 375 
 
 
 
 
 3 00 
 
 
 
 
 2. 75 
 
 
 
 
 3.00 
 
 
 
 
 2. 50 
 
 
 
 
 3.125 
 
 
 
 
 2.50 
 
 
 
 
 2.50 
 
 
 
 
 3.25 
 
 
 
 
 2.25 
 
 
 
 
 2.75 
 
 
 
 
 3.375 
 
 
 
 
 2. 25 
 
 
 Average 
 
 
 2.86 
 
 
 
 
 3.038 
 
 
 
 
 2. 485 
 
 
 : o 
 
 £ 
 
 a 
 
 
 
 +2 _: 
 
 o 
 
 • % 
 
 
 no 
 
 "© 
 
 
 <&A 
 
 m 
 
 
 
 
 
 
 
 ISA 
 
 * . 
 
 IS 
 
 a ~ 
 
 = = 
 
 *3 
 
 a 
 
 B 
 
 a f. 
 
 x "~ 
 
 
 — ~ 
 a .5 
 
 V 
 
 £a 
 
 a a 
 
 '■? a 
 
 r. a 
 
 cS 
 
 r 
 
 n*" 
 
 - CS 
 
 ri 
 
 a a 
 
 
 
 g a 
 
 a 
 
 ~a 
 
 fi 
 
 
 5 
 
 ""3 
 
 * 
 
 s 
 
 ~ 
 
 
 *" o 
 
 C rt 
 
 a 
 
 a 
 
 s 
 
 
 
 — 
 
 a 
 
 
 a 
 
 
 a 
 
 = 
 
 M 
 
 « 
 
 M 
 
 
 I M 
 
 M 
 
 M 
 
 
 M 
 
 
 1-1 
 
 M 
 
 Recapitulation : 
 
 
 
 
 
 
 
 
 
 
 
 Highest ! 3.50 
 
 1.3779 
 
 
 
 4.25 
 
 1.6732 
 
 
 sir ' 3. 
 
 50 
 
 1. 3779 
 
 7*S 
 
 Lowest 2.00 
 
 0. 7874 
 
 
 2. 25 
 
 '• 0.8858 
 
 
 A* 2. 
 
 00 
 
 0. 7874 
 
 T5S* 
 
 
 . 2.86 
 
 1. 1259 
 
 
 SS9 
 
 3.038 
 
 1.1960 
 
 
 sb 2. 485 
 
 0. 9783 
 
 T53I 
 
 
 Number of measurements 
 
 
 
 
 
 
 
 
 
 
 
 
 "1 
 
 27 
 
 
 
 
 20 
 
 
 
 
 29 
 
 
 
 
 Xumber of measurements 
 
 
 
 
 
 
 
 
 
 
 
 
 below average 
 
 23 
 
 
 
 
 30 
 
 
 
 
 
 21 
 
 
 
 
 Jrozier's 
 , from Ce 
 
 
 
 
 Crozier's 
 
 , 
 
 
 
 
 Croziers 
 
 
 
 French 
 
 vennes. 
 
 French Bla 
 Worms wl 
 
 ck. 
 lite. 
 
 
 
 Fr 
 W 
 
 ench Bla 
 onus da 
 
 Ck. 
 
 rk. 
 
62 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 The table will for the most part explain itself. The records of actual 
 measurements are stated in centi millimeters, and at the foot of each col- 
 umn of these is given the average of the thirty measurements represented 
 in each one respectively. 
 
 In the recapitulation we give reductions of these averages to thou- 
 sandths of an inch, and to fractions of an inch expressed in the vulgar 
 fraction, in order that the figures may be more easily comprehended by 
 all to whom they may be presented. In the same section we have given,, 
 similarly reduced, the highest and lowest measurements taken on each 
 sample, while in down lines will be found a series of figures showing 
 the number of measurements found above and below the average re- 
 spectively. These serve to show at a glance the range of the measure- 
 ment, and therefore express the degree of evenness and regularity found 
 throughout the length of the fibre of each sample. They will therefore 
 serve, to some extent, as an indication of the comparative value of the 
 several samples. 
 
 At the extreme bottom of each column is given a copy of the inscrip- 
 tion found on the box inclosing the sample represented. For the better 
 comparison of the several samples we may submit the following con- 
 densed table giving the averages of the measurements stated in centi- 
 millimetres and thousandths of an inch : 
 
 Number of samples. 
 
 S « . 
 
 S g § 
 
 o o 
 
 g ® 2 
 > a & 
 
 I 
 
 3.015 
 
 2.878 
 
 2.748 
 
 2.513 
 
 2. 465 
 
 2.528 
 
 2.86 
 
 3.038 
 
 2.485 
 
 1.1870 
 
 II 
 
 1. 1330 
 
 Ill 
 
 1.0818 
 
 IV 
 
 0. 9893 
 
 V. Yellow 
 
 0. 9724 
 
 Y. —White 
 
 0. 9952 
 
 YI. 
 
 1. 1259 
 
 YII 
 
 1. 1960 
 
 VIII 
 
 0. 9783 
 
 
 
 The differences here shown appear to be sufficiently wide to illustrate 
 any differences in the condition of feeding and management to which 
 the worms may have been subject during their development, but the 
 data we have will not warrant our entering into any discussion of these 
 interesting relations. There can be no doubt, however, that the com- 
 plete history of the worms will furnish material for exceedingly inter- 
 esting and valuable comparisons in this particular. 
 
 Measurements of strength and stretch. — The determinations of the tensile 
 strength of the fibres were effected by the aid of a dynamometer spe- 
 cially constructed for use in the examination of wools and cottons, 
 and described in "A Preliminary Eeport on the Examination of Cotton " 
 submitted to the Honorable Commissioner of Agriculture in 1882. This 
 
TESTS OF THE STRENGTH OF SILK FIBRES. 63 
 
 instrument is so constructed that the strain to which the fibre is sub- 
 jected to break it, and the stretch it sustains previous to rupture, are 
 simultaneously taken and recorded, and we have, therefore, to present 
 in this connection two sets of results. 
 
 In making these tests the following- method was employed : In the 
 first place the cocoons were cut open and their layers separated, or they 
 were submitted to the action of hot water and the fibres wound off upon 
 pieces of card-board, each process furnishing the "dry" and u wet" 
 specimens respectively described in a preceding paragraph. From the 
 loose fibre thus obtained sections of suitable length were taken at ran- 
 dom for the individual tests, the "wet" specimens having been previ- 
 ously thoroughly dried. The two clamps holding the fibres in the in- 
 strument during the tests were carefully set at a distance of 20 milli- 
 meters apart, so that this distance represents the length of the fibre 
 submitted to the strain. Experiments with woolen fibres showed this 
 distance to give the most uniform and satisfactory results, and is, there- 
 fore, accepted as a standard for all our work. Although no special ex- 
 periments were made with this regard on the silk examined, there is 
 little doubt that it would be found equally satisfactory. 
 
 In this part of the examination as in the measurements of fineness,, 
 we have adopted 30 as the best number of fibres to be tested to secure a 
 satisfactory average, and as before, each separate result obtained was 
 entered upon the record to be employed in any comparisons that it may 
 appear to be desirable to name. For their more ready comparison the 
 results obtained with the "dry" and "wet" specimens, respectively, are 
 placed side by side. The following table contains the results we have 
 obtained : 
 
64 
 
 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY 
 
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TESTS OF THE STRENGTH OF SILK FIBRES. 69 
 
 Here, as before, we have given the actual measurements taken, the 
 strains being stated in grams and the stretch in millimeters and per 
 cents. In the recapitulation we have prepared a statement showing 
 the averages of all the measurements taken with each sample respect- 
 ively, as well as the highest and lowest results obtained in each, the 
 strain in each case being reduced to grains and the stretch to per cents 
 of the length. This will make the figures more intelligible to all who 
 may be interested in them, and will render a comparison much more easy. 
 In the lower lines we find a statement showing the number of measure- 
 ments found above or below the average, as the case may be, for each 
 sample. 
 
 In explaining the method of measuring the fineness reference has 
 been made to the peculiar structure of the fibre, resultiug from the 
 mode of its production. This structure was decidedly marked in " dry " 
 No. V. Here very many of the fibres were split either before the test 
 or became split by the strain or at the instant of rupture. We find 
 upon comparison of the results obtained in the tests of the split fibres 
 in tests of whole fibres from the same cocoons that the latter are very 
 considerably stronger than the former, though as regards the percent- 
 age of stretch there appears to be no very material difference between 
 the two. And another peculiarity in the relations of the two is that the 
 strength of the whole fibre appears from the averages to be about double 
 that of the split fibres. Let us bring these averages together for more 
 ready comparison. It will suffice to express the strain as grams : 
 
 Split. Whole, 
 grains. ; grams. 
 
 V (dry vellow) 4.28 8.32 
 
 V (dry white) 3. 85 | 6.29 
 
 On the other baud it may be mentioned that the uniformity in the 
 strength of the fibres as regards the strain they are able to bear pre- 
 vious to rupture, as represented in the number of measurements found 
 above and below the averages respectively, appears to be greater in the 
 split fibres. The most important difference appears therefore to be in 
 the strain representing the strength of the fibre, showing the impor- 
 tance of the more complete cementation of the fibres together as they 
 issue from the spinnerets of the worms ; and we may also learn from this 
 something of the importance of maintaining the healthy and vigorous 
 condition of the worms during their development, and more especially 
 during the period when they are spinning their cocoons. The vigor 
 and activity of the insects at the time may be very materially stimu- 
 lated by careful regulation of the temperature, ventilation, and light, 
 and not only the value of the fibre with this regard, but the condition 
 and appearance of the cocoon, upon which its market value largely 
 depends, may be modified by these relations. In this rather critical 
 
70 
 
 BULLETIN NO. 3, DIVISION OF ENTOMOLOGY. 
 
 period of the insect's existence, when from the circumstances the extreme 
 care maintained throughout its development is likely to be relaxed, the 
 silk-grower should be particularly watchful and observe the greatest 
 care in keeping up the most favored conditions for the changes the 
 young insect is about to undergo during the period here referred to. 
 
 These considerations will also serve to attract attention to the im- 
 portant influence of the methods employed industrially in reeling the 
 silk from the cocoon upon the value of the staple. We have seen that 
 when the separate fibres issuing from the spinnerets of the worm are 
 fairly cemented together they are stronger than when they are hot thus 
 combined. And if we look over the Table II, given above, we shall find 
 that when the cocoons have been wet, or have been soaked in hot water 
 in order to separate the fibre, the latter as a general rule is stronger 
 than when it has been separated dry. In the process of reeling the 
 fibre becomes thoroughly soaked and saturated with water, so that the 
 glutinous character becomes perfectly developed. As a result the 
 primary fibres are more completely cemented together, while the ulti- 
 mate fibres brought into contact passing to the reel are combined so 
 perfectly that a maximum of strength must be secured. The influences 
 of moisture upon the strength of the fibres will be noted upon compar- 
 ison of the averages given in Table II. For convenience in making this' 
 comparison we have collected the necessary figures in the following 
 table : 
 
 No. of samples. 
 
 Average strain required 
 for rupture. . 
 
 Dry reeling. 
 
 Wet reeling. 
 
 I 
 
 8.36 
 8.25 
 5.78 
 7.68 
 8. 32 
 6.29 
 12.04 
 9.56 
 8.59 
 
 11.43 
 12.39 
 9.36" 
 9.33 
 7.80 
 9.81 
 11.18 
 11.05 
 6.97 
 
 II 
 
 Ill 
 
 IV 
 
 
 V (white) 
 
 VI 
 
 VII 
 
 VIII 
 
 
 We find here that, as a general rule, the higher results are in favor 
 of the fibres that were reeled wet. The exceptions found are in sam- 
 ples V (yellow), VI, and VII T, and these may doubtless be explained by 
 facts in the history of which we are not in possession. 
 
 In the table of results obtained with the dynamometer we have, as 
 in the preceding relating to fineness, given in the recapitulation the 
 highest and lowest as well as the. average of the measurements taken. 
 Below these may be found statements showing the number of measure- 
 ments found above and below the average respectively. These figures 
 serve to show the uniformity of the fibres with regard to the qualities 
 represented. The extension of the fibre under the strain necesssary to 
 
TESTS OF THE STRENGTH OF SILK FIBRES. 7 I 
 
 rupture is expressed in millimeters in a length of twenty millimeters of 
 fibre, as well as in per cents. Xo special experiments were made to 
 determine the limits of elasticity, and though the stretch will vary 
 somewhat with the length of fibre held between the clamps of the in- 
 strument, limiting thus the character of the results, yet for the purpose 
 of comparison the Figures we have given will prove amply sufficient, 
 and they will clearly show the differences in the quality and value of 
 the samples submitted to examination. 
 
 Other- qualities of the fibre and the cocoons have suggested them- 
 selves for investigation in the course of this work, but their examina- 
 tion has been precluded by the limited time at our disposal for the 
 present study of this staple. We, therefore, submit these results in the 
 hope that they may serve the ends desired. 
 
EXPLANATION TO PLATES. 
 
 PLATE I. 
 
 COSSUS CENTERENSIS. 
 
 1. Group of eggs as deposited, natural size. 
 
 2. Egg magnified 9 diameters. 
 
 3. Caterpillar from time of emerging to October 14 — four months' growth 
 
 4. Caterpillar of one year and four months' growth. 
 
 5. Caterpillar of two years and four months' growth. 
 
 6. Mature caterpillar, three years old ; ready to pupate. 
 
 7. Pupal cell. 
 
 8. Male pupa. 
 
 9. Female pupa. 
 
 10. Male Cossus, unspread. 
 
 11. Female Cossus. 
 
 12. Female Cossus, showing ovipositor. 
 
 PLATE II. 
 
 COSSULA MAGNIFICA. 
 
 1. Pupa case of Cossula magnifica. 
 
 2. Cossula magnifica. Male. 
 
 3. Cossula magnifica. Female. 
 
 4. Cossus querciperda. Male. 
 
 5. Cossus querciperda. Female. 
 
 6. Cossus angrezi. Female. 
 
 PLATE III 
 Silk fibres. 
 
 1. Fibre of white Cevennes race. 
 
 2. Fibre of Crozier's black race. 
 
 (Both figures magnified 240 diameters.) 
 
 (72) 
 

 
 : 
 
 
Bulletin 3, Division of Entomology. Department of Agriculture. 
 
 Plate I. 
 
 
 % 
 
 € 
 
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 | 
 
 COSSUS CENTERENSIS. 
 
Bulletin 3. Division of Entomology, Department of Agriculture. 
 
 Plate II. 
 
 1, 2, 3. COSBULA MAON1FUA. 4, 5. COSSUS QUERCIPERDA. 6. COSSUS ANGRKZI. 
 
UNIVERSITY OF FLORIDA 
 
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 3 1262 09216 5702 
 
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