88 Journal of Comparative Neurology, 



transverse ridge which overhangs the thin attenuated roof of the 

 medulla." 



1891. Herrick (13, 5-14) describes his investigations upon 

 the brains of rodents and certain reptiles. He obtains results 

 which throw a new light upon the cerebellum and mark an epoch 

 in the study of its histogenesis. He has discovered proliferat- 

 ing regions in the epicoelian roof which apparently are identical 

 with the writer's lateral protons. 



Professor Herrick makes a strong plea for the application 

 of the comparative method to the study of neurologic prob- 

 lems. To this argument, the writer joins his most hearty sup- 

 port. 



1 89 1. His (15) discusses the development in the human 

 brain of the region from the isthmus to the myel, during the 

 period from the end of the first to the beginning of the third 

 month. He includes the entire region under one segment, the 

 Rautenhirn, but does not deal especially with the cerebellum. 



1892. His (16, 373-375) gives a brief description of the 

 development of the cerebellum. He says, "The embryonic 

 epencephal (Hinterhirn) appears as a conical tube of which a 

 portion of the metatela (Rautenfeld) forms a part. Its caudal 

 limit is at the pons flexure; its cephalic, if we first subtract the 

 constituents of the isthmus, is at the isthmus flexure. Between 

 the pons flexure and the isthmus flexure lies the dorsally con- 

 vex j^knee of the epencephal. The metatela narrows rapidly 

 caudad from the knee, but a narrow extension of it whose edges 

 are nearly parallel extends cephalad. The floor of the metepi- 

 ccele (fourth ventricle) is formed from the ventral zone (Grund- 

 platte), the cerebellum from the dorsal zone (Fliigelplatte). Its 

 hemispheres are formed in the higher vertebrates from the part 

 of the dorsal zone lying caudad of the knee, the vermis from 

 the part lying cephalad of it." 



1893. Schafer (27, Vol. I, Part I, 66) says, "The roof 

 of the fourth ventricle inferiorly becomes greatly thinned and 

 expanded. Superiorly the tube becomes gradually more con- 

 tracted and the roof thicker. This thickening being the rudi- 

 ment of the cerebellum and of the valve of Vicusscns. In the 



