8 'Journal of Comparative Neurology and Psychology. 



loidonotus grunniens). It may be termed the sinus rhinalis, or 

 probably better, the fovea limhica. The lateral mass will be 

 called the lohus olfactorius posterior, or area olfactoria posterior 

 lateralis. Still farther back the striatum itself exhibits a more 

 important dorso-median enlargement and accordingly occupies 

 a higher position than the lateral mass, which in consequence is 

 depressed in a lateral direction in such a way that the configura- 

 tion in Lophius becomes exactly the same as in Gadus {cf. Figs, 

 iv, V and vi with Figs, viii and ix). The morphologic distinction 

 between these two parts will be demonstrated later by the descrip- 

 tion of the different tracts with which they are in connection. 



These parts may be distinguished more clearly than in the 

 smaller fishes in Gadus morrhua, where the difference in the 

 courses of the various olfactory fibers is very apparent (Fig. vii). 

 Bellonci has sharply distinguished them as lateral and medial 

 tracts, and they were also carefully examined by C. L. Herrick, 

 Edinger and Hamilton and Goldstein. 



While the medial tractus olfactorius runs caudad nearly in the 

 original direction, the lateral one deviates more and more to the 

 side and, situated in the sinus rhinalis, or fovea limbica, runs to 

 the area olfactoria posterior lateralis, as Professor Edinger, Dr. 

 Goldstein and I in conference have decided to call this part of 

 the fore-brain in the future. Bellonci called the place where 

 the outer thinner olfactory tract ends, "corteccia del emisfero," 

 and C. L. Herrick characteristically called it "hippocampal 

 lobe" because it seemed to be the physiological homologue of the 

 lobus hippocampi of higher vertebrates. Since, however, the 

 latter names suggest a more developed cerebrum than this area 

 exhibits, we choose the name first mentioned and likewise prefer 

 to call the tract just described the lateral olfactory radix instead of 

 tractus hulho-corticalis. 



The way by which the lateral fibers reach this point is not 

 always so short as it has been described for Gadus. Dr. Gold- 

 stein showed in his paper on the fore-brain and 'tween-brain that 

 in the fishes which he examined these lateral fibers cross through 

 the commissura anterior and then end in the area olfactoria 

 posterior lateralis of the opposite side, which I am able to confirm 

 for the greater part of these fibers in Salmo salar, preparations of 

 which have been given to me by Professor Rudolf Burckhardt, 

 to whom I am greatly indebted for his kindness. In an adult 



