70 Journal of Comparative Neurology. 



in fishes and reptiles the original spongioblastic skeleton persists 

 and may be easily made out in properly prepared sections of 

 the optic tectum and other regions extending from ectal to ental 

 surfaces. Moreover the much-mooted " gelatinous tracts " are 

 frequently but the elongated fibre-like connections between the 

 two free surfaces which have been separated by the distortions 

 due to growth. Compare Plate XXVIII, Figs, i and 7 in 

 Festschrift f. Leuckart, and discussion on p. 45-46 of this Jour- 

 nal for May, 1892. In an article in the Denison Quarterly, re- 

 published in this journal for Dec. , 1892, pp. 141-142, the or- 

 igin of the cerebellar elements from proliferations of epithelial 

 origin is again described. On p. 86 of the June number for 

 1893, is a discussion of the primary or transitory layer in the 

 cerebrum. See also Anatomischer Anzeiger, VII, 13, 14. 

 Dr. Schaper deserves great praise for his thorough study of the 

 subject and it in no way detracts from the merit of his work to 

 call attention to the fact that he does not stand alone in his po- 

 sitions. 



