132 Journal of Comparative Neurology. 



subject of his paper. His studies however are exclusively 

 macroscopic, no attempt having been made toward the prepara- 

 tion of sections for the study of its finer anatomy. 



KopscH obtained his specimen from the zoological gardens 

 of Berlin. It comprised the entire medulla spinalis with the ex- 

 ception of the 1st and Ilnd cervical segements, which were 

 removed in company with the head. Unfortunately both 

 these and the head were unavailable. The animal was a male 

 ElepJias indicus. Its age, probable weight and cause of death 

 are not given. 



His description begins with the specimen in situ. He was 

 able to proceed by removing the neural arches from the columna 

 vertebralis and thus could observe the medulla spinalis enclosed 

 by its meninges and lying in its natural position in the canalis 

 vertebralis. Since the specimen at the disposal of the author 

 had been removed and was even devoid of its dura mater, the 

 author had no opportunity to observe it with reference to its 

 environment. This fact is offered as an additional reason for 

 giving a more detailed review of certain parts of Kopsch's pa- 

 per. Also, wherever the author has been able to examine fea- 

 tures retained in his specimen and also touched upon by Kopsch, 

 the observations made upon the two specimens will be com- 

 pared. 



After laying bare the specimen in the canalis vertebralis, 

 Kopsch noted many fibrous connective tissue bundles joining 

 the dura mater with the wall of the canalis vertebralis. These 

 traversed a relatively wide epidural lymph space which, in man, 

 is occupied by the internal plexus venosus vertebralis and con- 

 siderable adipose tissue. The latter was absent in the elephant 

 Kopsch examined. 



Next, the dura mater was opened by a median longitud- 

 inal slit and laid back so that the medulla spinalis proper could 

 be observed and the relation of its segments to those of the 

 columna vertebralis could be determined. 



The cavum subdurale was relatively capacious as Owen had 

 previou.sly noted. The conus meduUaris terminated in the ca- 

 nal of the 1st sacral vertebra and the filum terminale continued 



