100 Bulletin of Laboratones of Denison Uniefvsity. [Voi. xiii 



ipheral gustatory terminals of the first order and their neurites 

 either descend to the inferior secondary gustatory nucleus in 

 the region of the funicular nuclei or ascend to the superior sec- 

 ondary gustatory nucleus in the isthmus. In both cases the 

 path is mainly and perhaps exclusively gustatory in function. 



'""^^nsr^^ 



Fig. 38. Diagram ot the gustatory paths in the brain of the carp as seen 

 from the side. Only the long paths are shown in this diagram (cf. Fig. 39). 



ti.VII.s., n.IX.s., and n.X.s., represent tlie sensory root fibers of the facial- 

 is, glossopharyngeus and^ vagus respectively, or gustatory neuronefe of the first 

 order .(/). The secondary tracts, both ascending and descending, are marked 

 //. The tertiary path to the inferior lobe is marked ///; the path to the cere- 

 bellum and valvula, in. The return path from the inferior lobe to the motor nu- 

 clei of the oblongata (ttactus lobo-bulbaris) is marked IV. The commissures of 

 the inferior and superior secondary nuclei are indicated by shaded areas ( the lat- 

 ter marked c). n.op., the optic nerve. The area marked n.fun. includes the 

 funicular nucleus and the inferior secondary gustatory nucleus. 



In cyprinoids the gustatory neur'ones of the smaller type proba. 

 bly share both this function and that of the intrinsic neurones. 

 In no case does a peripheral gustatory neurone connect direct- 

 ly with a peripheral motor neurone. There is always at least 

 one intermediate neurone between them. 



The vagal lobes of the larger cyprinoids differ from those 

 of the siluroids, in addition to the points already mentioned, in 

 the following respects: (i) The chief secondary neurones, be- 

 ing exceedingly numerous and crowded in a narrow peripheral 



