FEATURES OF THE NEURAL STRUCTURE 



59 



sectioning and staining the cortex its numerous functional divisions are 

 at once obvious by the differences in the cells and fibers. The brain-cells 

 have no obvious capsule. In the ganglia of the peripheral nerves are 

 medium-sized nerve-cells which have around them the neurilemma. In 

 the sympathetic system and in other places are cells surrounded by 

 "baskets" of nerve-fibrils, connecting with a more or less distant cell. 



FIG. 27 



a 



The effects of overstimulation (fatigue?) on the motor nerve-cells of a cat: a, normal; 6, after 

 five hours' continual stimulation. (Hodge.) 



Frog 



Lizard 



Man 



The phylogenic and the ontogenic evolutions of the pyramidal nerve-cell and the neurone. 

 The top row of neurone?" (from left to right) are those of the frog, the lizard, the rat, and man, 

 respectively: a, b, c, d, e are stages in the embryological development of the pyramidal j\sell. 

 (Ramon y Gajal.) 



