452 PROFESSOR a. elliot smith. 



words, they virtually adopt a definition of the " rhineiicephalou " 

 such as I have suggested in these notes. 



Others, again, reach the same end without confusing the 

 hippocampus and the so-called " hippocampal gyrus." Thus, in 

 a recent work,^ the writers commence with a tabulation of the 

 teaching of His and the Nomenclature Commission (page 1) ; 

 they then describe the brain of the Chimpanzee, and exclude 

 from their rhinencephalon not only the hippocampus, but also 

 the pyriform lobe (p. 45). In other words, they follow the 

 tabulated list of the Nomenclature Commission, but appear to 

 forget that this same Commission also stated (vide supra) that 

 the rhinal fissure ("Jissnra rhinica " of Turner) is the line of 

 demarcation between pallium and rhinencephalon. Toward the 

 end of the work, however (p. 550), the authors include both the 

 pyriform lobe and the hippocampus in the rhinencephalon j 



Conclusion. 



In these fragmentary notes my principal object has been not 

 so much to seek for a more logical interpretation of the term 

 " rhinencephalon" as to call attention to the exact limits of the 

 neopallium. For if we retain the term " pallium " in its present 

 sense as a complex of neopallium and hippocampus, the greatest 

 confusion will be perpetuated in the language of Comparative 

 Anatomy. Thus, a writer on the Sauropsidan l)rain will speak 

 of the " pallium " of a lizard or bird when he refers to what is 

 chiefly hippocampus ; and the unwary reader may imagine that 

 it is the same "pallium" as that of Man, which, however, is 

 chiefly " neopallium." ^ But it is high time that some distinctive 

 name should be found for that great progressive cortical field, 

 the high development of which becomes in the Mammalia the 

 great fundamental condition of their survival. At every epoch 

 in the history of the mammal this part of the brain shows a 



' Flatau and Jacobsoliii, Virgl. Anat. d. Centralncrvcnsystems, 1899. 



- Tliis confusion is nowhere more pronounced than it is in the writings of 

 certain anatomists wlio call the hii)pocam{)al commissure of Reptiles and Birds 

 the " coniinlnsara pallii." Boy ce and Warrington even call other hippocampal 

 tracts "pa/Hal" [Phil. Trans., 1899, p. 29G). 



