trt.b. 



Fig. 23 Section immediately in front of the tuberculum posterius. Some , 

 details of the neurons are added from the two adjacent sections rostrad and 

 caudad. Dendrites of neurons of the tectum spread out in the area of distri- 

 bution of the optic tract (col.sup.) and also farther ventrally in the colliculus 

 inferior (col.inf.). In the motor tegmentum are three neurons of the nucleus 

 of the posterior commissure (nuc. com. post.) and two of the nucleus of the 

 tuberculum posterius {nuc. tub. p.). The dendrites of the tectal neurons tend 

 to develop tufted glomerulus-like terminals, in contrast with the more open 

 and smoother terminals of those of the motor tegmentum. The locations of 

 some of the fiber tracts are indicated on the figure, though to avoid confusion 

 they are not drawn (cf. fig. 24, three sections farther caudad, where these tracts 

 are drawn). In this section terminals of the acoustico-lateral lemniscus and 

 spino-tectal tract are freely spread out in the colliculus superior substantially 

 as shown in figure 24. X 74 (cvic, 178). 



316 



