148 Journal of Comparative Neurology and Psychology. 



of very large numbers of non-meclullated fibers in the spinal iierve.s 

 of the rabbit by the method of Cajal. These non-medullated fibers, 

 an account of which will appear in another paper, allow us to cxplaiu 

 with ease the following otherwise inexplicable facts : 



1. The axonal reaction in the small cells which are not connected 

 with medullated fibers in the nerve. 



2. The results of Lugaro, Fleming, Cox, Cassirer, Koster, War- 

 rington and Griffith, and myself which show that the vast majority 

 of all the cells in the spinal ganglion react to a lesion of the 

 peripheral nerve although only a small part of these cells are con- 

 nected Avith medullated fibers in the nerve. 



3. The degeneration of 4412 ganglion cells after the section 

 of a nerve containing 1500 medullated fibers. These 4412 cells 

 were chiefly small cells and were associated with non-medullated 

 fibers in the nerve. 



4. The intact condition or only slight degeneration of the dorsal 

 roots after the degeneration of 52 per cent of ganglion cells, the 

 average loss in the dorsal root being 17 per cent. This is easily 

 understood when it is remembered that the large cells which alone 

 are associated with medullated fibers in the dorsal root pass rapidly 

 through the phases of reaction and repair to complete restitution. 



BIBLIOGRAPHY. 



BUMM, A. 



'0,3. Die pxiun-imeutelle Diu-ebtvi'inuin;,' dor vordern und liintern 

 Wurzel des zweiten Halsnerveii bei der Katze luid ilire 

 Atrophiewirkuug avif das zweite spinale Halsgauglion. BHz. 

 Bcr. Gcs. MorpJi. Physiol.. Miinclieii, B. 18, p. G.5. 



Cox, W. II. 



'98. Der feinere Ban der Spinalgauglienzelleii des Kanincliens. Aiutf. 



Hcfte, Abtb. 1, Bd. 10, Heft 31, p. 73. 

 '98a. Beitriige zur patbologischen Histologie luid Pbysiologie der 



Ganglienzellen. Internat. MoiKitsscJir. fiir Aiiat. und Pliys., 



Bd. 1.5, p. 241. 



Cassirer. IX. 



'99. Ueber Yeriinderungen der Spinalganglienzelleu nnd ibrer cen- 

 tralen Fortsiitze nach Dnrebscbneidung der zugeborigeii peri- 

 pberen Nerveii. Deutsche Zeitxchr. fiir Nervciihcil., Bd. 14. 

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