PHYLOGENY AND ONTOGENY OF NEURONA 57 



Cerebral Cortex of Birds. The body of the 

 neurona here makes a marked advance in its 



FIG. 9. 



Cerebral cortex of birds. A, molecular sheath ; B, sheath of little starred 

 cells ; C, sheath of large starred cells ; D, sheath of deep starred cells ; 

 E, epithelium ; a, pyramidal cell with its peripheric (p) and basal (d) 

 protoplasmic expansions ; the cylindric axis ; c, e, neuroglic epithelial 

 cells; 7i, s, neuroglic cells of the neuroglic epithelia. (According to 

 Sola. ) 



