IIB 



iistributei at irretSular intervals in the peripharil region of 

 the cell. 



4. Support lig ElemeitH . 



Associatei with tne many ani crowiei nerva-traots charac- 

 terising the structure of the interbrain, there is to be notei 

 a corresponiing de\^elopinent of both neuroglia and epeniyma. 



A neurogliar eleinent has a few stout processes raiiatin^ 

 in every direction from the cell-body, often pursuing a marked- 

 ly tortuous course. They raiiify in an exceedingly complicated 

 manner, the finest t^igs interlacing to form a dense mat; see 

 Pig. 89. Neuroglia is found in the nuclei of the interbrain, 

 serving to support both the neurones and the terminal fibres 

 occurring there. 



Spendyma is found in all parts of the interbrain. The 

 epeniymal fibre al-rays extenls throughout the entire thickness 

 of nervous matter, from the ventricle to the limitans externa. 

 The fibre branches mid/»ay in its course, the several limbs often 

 diverging considerably. The entire fibre-system bears a multi- 

 tude of fine mossy processes. These features are sho/»n in Fig. 30. 



-5. Summary of the Interbrain. 

 The thalair.us is small in size and has remained on a low 

 plane of differentiation. It is practicable to distinguish 



