Irtpedp. 

 ped 

 t.\.m 



com.tub.p. 



col.int 



coLint 

 tr5p.T.tti:sp.lh.\ 



nuc.HI. 



TrspT.+Tr 

 sp. Ih. 



Trtped.p. 

 fvt 



Fig. 31 Through the tuberculum posterius in the same plane as figure 10. 

 Comparison of figures 31 to 35 with figures 10 to 14 shows that in the former 

 series the tectum mesencephali has collapsed into the optocoele producing some 

 distortion of the tectum. A single neuron of the colliculus inferior (col.inf.) 

 is impregnated, some of its dendrites spreading throughout the field of the 

 acoustico-lateral lemniscus and others extending farther ventrally into the cere- 

 bral peduncle. The axon is directed ventrad, probably to enter the tractus 

 tecto-bulbaris or tecto-peduncularis profundus. Dendrites of several neurons 

 of the cerebral peduncle are impregnated (ped.). X 30 (cvc, 3-4-1). 



Fig. 32 At the level of the superficial origin of the III nerve; cf. figure 11. 

 In this and the next following figure the stratum griseum of the tectum mesen- 

 cephali is coarsely stippled; that of the pedunculus cerebri is unshaded. On 

 the left side two neurons of the optic part of the tectum (col. sup.) are impreg- 

 nated, one of which sends dendrites also into the colliculus infei'ior (col. inf.). 



322 



