440 



PROFESSOR G. ELLIOT SMITH. 



clefiuition of a " rhineucephalon " to other mammalian brains, 

 but many of his followers have attempted to do so.^ 



His includes in the " Eiechlappen " the " hulbus," " tractus " 

 (i.e.,pedunciilus) and " to'igonum olfactorium" the '■^ area imrol- 

 fadoria Broccc," the " gyi-us suhcallosus," and the locus perforatus 

 anticus. The last two of these regions are separated, upon 

 supposed embryological grounds,- as a lobus olfadorius ijostcrior 

 from tlie rest, which constitute a lohus olfadorius anterior. If 

 we examine this grouping of cerebral areas in the light of Com- 



01 factor}' bulb. ■ 



Corpus striatum. — — — 



Pyriform lobe. 



\ 



\ 



Optic thalamus. 



Hippocampus. 



Fig. 5.— Diagram representing a horizontal section through the two cerebral 

 hemispheres of the typical brain, on a plane ventral to the rhinal iissure. 



parative Anatomy, its value as a natural division is found to be 

 very slight. In the first place, it includes the gyrus suhcallosus 

 of Zuckerkandl, and excludes the septum lucidura, both of 

 which are parts of one and the same histological formation, the 

 paraterminal body, which forms a natural and indivisible area 



1 A typical example of such an attempt is alfordeil by a recent work by Flatau 

 and .Tacobsohn, to which Professor Wahleyer has given his countenance. 



2 In regard to this point, see lloclistetter's masterly exposure of the nature 

 of so-called " transitory fissures," Bibliotheca, Mcdica, A. Heft 2, 1898. 



