52 



SUPER-ORGANIC EVOLUTION 



As our object is to make known these funda- 

 mental facts in the simplest form, we try to simplify 

 the ideas and denominations, with the idea of 

 everyone seeing their supreme importance without 

 their signification being lost. The bipolar form is 



FIG. 6. 



Cells of the olfactory mucous membrane of a rat eight days old. e, epithelial cell 

 or support ; n, bipolar cell (neuro-epithelial) with a superficial end provided 

 with several free appendices, fine and non-vibrative, a little body, oblong 

 or fusiform, where a nucleus is lodged ; and, b, a deep expansion which is 

 continued by a fibre of the olfactory nerve. (According to S. R. y Cajal. ) 



not exclusive to the lower animals, as it is found in 

 the mammiferae and also in man. 



The illustration fig. 6 represents the type of bipolar 

 neurona, and it has an important signification, as it 

 shows that the simplicity of form in the neuronas 



