Kappers, Teleostean and Selachian Brain. 35 



Before proceeding to describe the tracts of the lobi inferiores 

 it should be stated that they have a small ventricle, correspond- 

 ing to the inferior part of the third ventricle. This vcntric- 

 uliis lobi inferiores is indented from below by a cell mass 

 which gives it a falcate form in Gadus (Figs, xlvi, xlvii). The 

 free caudal ends of these lobes extend caudad under the mid- 

 brain beyond their place of attachment, which is marked by 

 the roots of the nervus oculomotorius (Lophius, Fig. xxxii; 

 Gadus, Fig. li). 



Now I proceed to the description of the tracts which originate 

 from or terminate in the hypothalamus or pass through it. They 

 will be divided into several groups: 



1. Tracts connected with the tuber cinereum. 



2. Fibers belong-ing to the saccus vasculosus. 



3. Tracts which relate the groups of cells under and before the 

 ventriculus opticus with the lobi inferiores. 



4. Mutual relations of regions of the lobi inferiores themselves. 



5. Relations of the hypothalamus with frontal parts. 



6. Relations of the lobi inferiores with caudal parts. 



To the tracts of the first group belong two which have already 

 been mentioned, (i) The tr. prcethalamo-cinereus (Figs, xxxv 

 to xxxviii) which comes from the nucleus praeopticus (Fig. xi = 

 nucleus magnocellularis strati grisei, Edinger, Goldstein) and 

 terminates in the tuber cinereum. (2) The group of cells where 

 this tract terminates and to which Goldstein gave the name of 

 nucleus anterior tuberis is connected with the corresponding group 

 of the opposite side by the comnnssura tuberis, of which mention 

 was made when speaking of the praeinfundibular connections 

 (Fig. xxxviii). 



(3) To these I have still to add another tract, whose origin is 

 also situated in this region. In Gadus it is composed of small but 

 compact feebly medullated bundles which first run upward 

 (Figs, xxxix, xl) and then backward along the third ventricle and 

 end in the anterior part of the lobi inferiores (Figs, xli, xlii), the 

 tractus lobo-cinereus brevis. In Thynnus, however, the whole 

 tract is much more developed than in Gadus, Lophius or Salmo 

 and undoubtedly the greater part of the fibers which originate in 

 this place and in separate bundles in the same way go higher up 

 and end, after turning outward, in the region of the nucleus 

 lentiformis, under the optic ventricle. This is the same tract 



