22 'Journal of Comparative Neurology and Psychology. 



describes their situation in the recessus praeopticus but reckons 

 them to the nucleus taeniae because he saw fibers going from them 

 to the gangha habenulae. I call especial attention to the literary 

 notices upon this point because I wonder that so eminent an 

 investigator as Edinger does not mention this nucleus in the 

 fishes, where its existence and situation are so evident.^ 



As for the fibers which pass out from this nucleus obliquely 

 downward and laterally (Figs, xxxiv to xxxviii) as C. L. Herrick 

 has described them, I can confirm in the teleosts Johnston's 

 observation for Acipenser, that, curving backward at the brain 

 floor, they run down parallel to the tr. strio-thalamicus and reach 

 the anterior part of the infundibulum, the tuher cinereum^ (Fig- 

 xxxviii). I think that I could name this bundle, which Johnston 

 does not designate by a special name, most simply as tractus 

 prcethalamo-cinereus. 



Now, having described this praethalamic nucleus and the tract 

 belonging to it, I may take up the bundles coming from the fore- 

 brain, of which I have already described in a broad way the tr. 

 olfacto-lobaris {or hypothalamicus) medialis, when treating of the 

 fore-brain, and mentioned the literature on the subject. It is 

 seen again in Fig. xxxiv et seq. and in Fig. xliv we see it reach its 

 terminus in and under the nucleus rotundus while turning mesad 

 around it. 



Along with this tertiary olfactory tract I must take up the second 

 olfacto-hypothalamic attachment mentioned in the first chapter 

 as the tractus olfacto-lobaris (or olfacto-hypothal amicus) lateralis. 

 Though so much has been written about the course of fibers in 

 this region, especially about the tractus strio-thalamicus, in the 

 teleosts, I have never found this tract mentioned except perhaps 

 by C. L. Herrick, who divides the "peduncles," as he calls the 

 tracts in this part of the thalamus, into two parts, a dorsal and a 

 ventral peduncle. The ventral peduncle is the tractus strio- 

 thalamicus, while the dorsal originates from the caudo-lateral 



'He may have described it as "nucleus magnocellularis strati grisei'' in the reptiles; also as "high 

 small nucleus of large cells lying by the side of the wall of the ventricle," though somewhat more caudad. 



After I had already written these pages Edinger told me that my supposition was right. Gold- 

 stein mentions the same nucleus in his work on the fore-brain and 'tween-brain of the teleosts and gives 

 it the same name which Edinger used for the reptiles. 



^C. L. Herrick may have described this attachment with the tuber cinereum as tract, tub. cin. 

 ad com. ventralis. 



