Art. II.] 



Herrick, Gustatory Paths in Fishes. 



77 



part of the "Uebergangsganglion" of Stieda. This group of 

 cells fuses behind with the dorsal and cephalic border of the 

 secondary gustatory nucleus, but is separated from it more or 

 less definitely by the medullated vertical cerebellar tracts which 

 encapsule the secondary gustatory nucleus. Sections stained 

 by the method of Pal show large tracts of fine fibers with ex- 



yahula cereb 



ce.rebe.llum 



tr.tl 



nuc. /at. 

 . va/y.y 



'gustatory 

 nuc. 



/obus inf. 



Fig. 2j. Portion of sagittal section of the brain of a young carp, 5 cm. long. 

 GoLc.i method. X 40. 



The ventral side of the preparation is below and the cephalic end at the left. 

 -The section includes the superior secondary gustatory nucleus ("Rindenknoten," 

 Mayser) and shows the origin and course of the tertiary path to the inferior lobe. 

 A single neurone of the latter type is impregnated completely {a) save for the 

 terminal arborization. Mingled with the neurites of these cells are those of the 

 tract between the cerebellum and the inferior lobe (tractus lobo-cerebellaris, 

 Edinger). Among the terminals of the tertiary tract are the cells of origin of 

 the tractus lobo-bulbaris et spinalis (tr.l.l>.)\ l.vi., lemniscus ; tr.t.l., tractus tecto- 

 lobaris ; tr.t.s., tractus tecto-spinalis. 



ceedingly delicate medullary sheaths passing dorso-ventrally 

 between the n. lateralis valvulae and the cerebellum and valvula 

 (Fig. 24), and Golgi sections show diffuse unmedullated tracts 

 taking the same courses (Fig. 20). Whether the medullated 

 and the unmedullated fibers spring from neurones of the same 

 type, I have not been able to determine. The neurones shown 



