OCCURRENCE 
 
 OF 
 
 MICROSCOPIC CRYSTALS 
 
 IN THE 
 
 VERTEBRAS 
 
 OF THE 
 
 TOAD. 
 
 H, CARRINGTON BOLTON. 
 
Digitized by the Internet Archive 
 in 2017 with funding from 
 
 University of Illinois Urbana-Champaign Alternates 
 
 https://archive.org/details/occurenceofmicroOObolt 
 
Ufl* 
 
 [Reprinted from the Proceedings of the American Association for the Advance¬ 
 ment of Science, Yol. XXVIII, Saratoga Meeting, August, 1879.] 
 
 
 On the Occurrence of Microscopic Crystals in the Verte¬ 
 bra of the Toad (Bufo Americanus). By H. Carrington 
 Bolton, of Hartford, Conn. With a Note by Alexis A. 
 Julien, of New York. 
 
 The microscopic crystals contained in the capsules attached to 
 the spinal nerve of the frog have been examined by many Histol¬ 
 ogists. They were first noticed, we believe, by the learned Flem¬ 
 ish physician, Blasius 1 in the latter part of the seventeenth 
 century. Swann, in his Comparative Anatomy of the Nervous 
 System , 2 gives figures of them without any detailed description, 
 and Wagner 3 refers to the crystals as follows: “The ganglia 
 admit of being very readily demonstrated, lying upon the sides of 
 the vertebral column ; they are situated near those small white 
 vesicles which protrude by becoming swollen, chiefly during the 
 
 1 Anat. Animalium, Amst. p. 291,1681. 
 
 2 Plate VII, figs. 5 and 6. 
 
 8 Comp. Anat. Vertebrates, part I., p. 151. 
 
 0) 
 
 p 37415 
 
2 
 
 MICROSCOPIC CRYSTALS ; 
 
 spring of the year, and contain numerous microscopic calcareous 
 crystals.” They were also observed by Stannius and by Prof. 
 Owen, who, however, added little to our knowledge of them. 
 
 In 1852 Dr. Jeffries Wyman prepared a memoir on the 
 “Anatomy of the Nervous System of Rana Pipiens,” which is 
 published in the fifth volume of the Smithsonian Contributions 
 to Knowledge, (1853). In this paper he states that the “ ciystal 
 capsules are subject to some variety, but exist on the trunks of 
 all the true spinal nerves, the hypoglossus included, and invest 
 them more or less completely at their exit from the spinal canal, 
 occupying the space between the transverse processes of two 
 adjoining vertebrae. The capsule is a very thin membrane, some¬ 
 times having a diameter of 2 to 3 lines ; its surface is minutely 
 lobulated in appearance, which results from the existence of 
 numerous partitions within, forming many small cavities, which 
 communicate, though not very freely, with each other. The 
 contents of these pouches are vast numbers of exceedingly minute 
 crystals of a somewhat oval form, pointed at their extremities, 
 and comparable in shape to a lemon seed, but sometimes pre¬ 
 senting well defined angles.” 
 
 Dr. Wyman failed to confirm Wagner’s statement that the 
 capsules are more swollen in the spring of the year, having, he 
 says, “detected them of nearly equal dimensions at all seasons,” 
 and he also differs from Stannius in regarding them as character¬ 
 istic of the adult animal. 
 
 Dr. W} 7 man then remarks: “Dissections of other than Rani- 
 form Batrachians have not led to their detection ; I have not 
 found them in Siren , Menobranckus , Bufo or Salamandra , but 
 have seen them in Rana fontinalis , Rana, halecina and Rana 
 palustris. They seem to be in these species constant appendages 
 to the spinal nerves.” 
 
 Notwithstanding this positive statement of so distinguished 
 and accurate an observer, the writer has found the microscopic 
 crystals in the toad in great abundance, and differing little in form 
 and general appearance from those occurring in the frog. Speci¬ 
 mens of the common toad ( Bufo Americanus) , collected both in 
 the autumn and in the spring were dissected, and in eveiw instance 
 the contents of the spinal canal examined under a \ inch object¬ 
 ive, disclosed the white matter as a mass of minute crystals. 
 
 On treating the crystals on a glass slide with acetic acid they 
 
BY H. CARRINGTON BOLTON. 
 
 3 
 
 dissolve with effervescence, and the addition of oxalate of ammo¬ 
 nium to this solution produces a milkiness visible to the unaided 
 eye, which under the microscope appears to be formed of minute 
 ovoid masses characteristic of precipitated calcium oxalate. 
 
 When the calcareous crystals are placed under the microscope 
 in a drop of water, they exhibit in a marked manner the phenom¬ 
 ena known as Brownian motions ; the larger crystals remain at 
 rest but the smaller ones having a length of about milli¬ 
 
 metre maintain a constant restless motion. That similar crys¬ 
 tals from the spinal canal of the frog exhibit this phenomenon is 
 well known to histologists. 4 
 
 The resemblance of the crystals from the toad to those from 
 the frog is very close, but a careful examination shows that the 
 former average somewhat smaller than the latter. Slides contain¬ 
 ing crystals from Rana and Bufo, mounted in Canada balsam, 
 were submitted for accurate measurements to my friend, Mr. 
 Alexis A. Julien, to whom I am greatly indebted for a pains¬ 
 taking examination. 
 
 Mr. Julien reports as follows : 
 
 “ The crystals appear perfectly colorless with sharp outlines 
 and with a refractive index so nearly that of the Canada balsam 
 in which they are mounted that it is difficult to distinguish any 
 but their outer edges. It will be seen b} r the measurements given 
 below that the average size and the variation in size of the Bufo 
 cr}’stals are the greater of the two. In the accompanying sketch, 
 Fig. 2, d, represents one of the larger of these crystals, exhib¬ 
 iting most distinctly the highly modified edges. In both the Rana 
 and the Bufo crystals many were observed which at first glance 
 displayed a curved or spindle-shaped outline tapering rather sud¬ 
 denly toward either end ; some of these are shown in Figs. 1 and 
 3. They are often of considerable size and by careful focusing 
 these curved outlines were found to consist of a succession of 
 straight edges, indicating simply a more highly modified form of 
 the common crystals. On the whole the crystals of both Rana 
 and Bufo appear to me to differ from the otoliths of aragonite 
 enclosed in the human ear, familiar to histologists, and to re¬ 
 semble rather highly modified rhombohedra of calcite belonging, 
 perhaps, to the type represented in Fig. 553 of Dana’s System of 
 Mineralogy. No twins were anywhere observed.” 
 
 4 Frey’s Microscopical Technology, translated by Dr. Geo. R. Cutter, p. 101 (1872). 
 
4 
 
 MICROSCOPIC CRYSTALS ; BY H. CARRINGTON BOLTON. 
 
 Size of Crystals infractions of millimetre. 
 
 Bufo. 
 
 Largest 
 Smallest 
 Common size 
 
 Length. 
 
 0-033 
 
 0-0005 
 
 0-0034 to 0*025 
 
 Breadth. 
 
 0-0140 
 0 0003 
 
 0-001 to 0-01. 
 
 liana. 
 
 Largest 0*0229 0*0074 
 
 Smallest 0-0007 0*0004 
 
 Common size 0-0068 0-0014 
 
 [Otoliths measure about 0*012 mm. long by 0-008 mm. broad. 5 ] 
 
 The accompanying figures from drawings by Mr. Julien show 
 the crystals as seen with a magnifying power of 900 to 1008 
 diameters, under the camera lucida. 
 
 Fig. 1 shows a portion of the field seen in the slide of Ran a crys¬ 
 tals and Fig. 3 shows the same in that of Bufo, with the usual 
 intermixture of perfect crystals and irregular fragments. Fig. 2 
 contains several individual crystals enlarged in the drawing. 
 
 POSTSCRIPT. — May, 1880. 
 
 Since preparing the foregoing notes Mr. Simon H. Gage, Instructor 
 in Physiology at Cornell University, has had the kindness at my sug¬ 
 gestion to extend the examination for calcareous crystals to other Am¬ 
 phibia. He reports as follows : 
 
 “Alcoholic specimens of Siren and Menopoma were very carefully ex¬ 
 amined, but no crystals could be found either in the neural canal or on 
 the spinal nerves. A fresh Menobranchus was examined with the same 
 result.” 
 
 Mr. Gage confirms our observation as to the occurrence of the crystals 
 in Bufo and in this connection remarks: 
 
 “In Rana the crystals ou the nerves are beyond, periplierad ox, the 
 ganglion and seem to have no connection with those lining the neural 
 canal; while in Bufo the ganglion is completely surrounded by a cushion 
 of crystals which seem to be merely a lateral extension through the in- 
 tevertebral foramina of the general cushion lining the neural canal. 
 
 Dr. Wyman in the paper quoted makes no reference to the crystals in 
 the neural canal of Rana.” 
 
 Mr. Gage’s communication is accompanied by a cross-section of the 
 spinal column of Bufo showing the exact position of the cushion of crys¬ 
 tals, and we regret that circumstances prevent a reproduction of his 
 sketch. 
 
 5 Dr. J. B. St. John Roosa in Diseases of the Ear, p. 475 (1874). 
 
 [Printed at the Salem Press, June, 1SS0.] 
 
r