Its Composite and Dissoluble Nature. t5i 



of which have scarcely one-fourth the diameter of their 

 superior neighbors. Many of these have small fibrillar 

 processes, one of which is sometimes seen to rise toward 

 the " molecular" layer, while the other dips downward 

 amidst the white fasces of fibers. The function of these 

 smaller nuclear cells is not easily divined. 



In the medulla oblongata and in the gray columns of 

 the spinal, .cord are also found lai'ge cells with branched 

 protoplasmic processes, somewhat resembling those of the 

 cerebellum, with small nuclear cells and fusiform or 

 spindle-shaped cells, in connection with the same mazy 

 hanks and bundles of communicating fibers. And in the 

 great hemispheres of the cerebrum, or grander brain, is 

 found an arrangement of superior cells and inferior cells, 

 with enormous hanks of fibers similar to that observed in 

 the cerebellum, but on a vaster scale. 



The superior and larger cells of the cerebral cortex 

 differ in form from the Purkinje cells, and from their 

 triangular outline have received the name of pyramidal 

 cells. They are found in great numbers and at varying 

 depths in the "molecular" gray cortex of the cerebrum. 

 The body of a large pyramidal cell averages about .04 

 mm. in length by .02 mm. in width. It occupies a free 

 space, is surrounded by blood capillaries which supply, it 

 with nutriment, and rests easily in lymph fluid, with a 

 number of protective cells and repair cells in close attend- 

 ance upon it. It is further supported by the nets of. 



