230 



JOHA'SrON. 



[VOL. I. 



for the cells of the fore-brain of the trout. The axis cylinders 

 arise from the side or apex of the cell body or from the first 

 portion of one of the basal or apical dendrites. Each fiber is 

 of medium thickness and quite smooth. It runs latero-ventrad, 

 grows distinctly more slender as it is traced further from the 



FIG. 2. Diagrammatic section of the fore-brain in the plane indicated by the dotted line in Fig. 4, a. 

 Outline, x 25 diameters ; cells, x 50 diameters. 



cell, gives off numerous collaterals which ramify widely in the 

 striatum, and ends with terminal branches in the external por- 

 tion of the striatum. All my preparations contain many cells 

 of this sort. 



The external nucleus (Figs. 2, 3, Striatum) is composed of 

 irregular cells with two or more dendrites, which are not 

 arranged in layers and are not so compactly grouped as are 

 those of the internal nucleus. The cells measure 12 to 24 by 



