146 



COMPARATIVE ANATOMY 



Fig. 108. — Types of nerve cells. A, multipolar cell; B, portion of nerve fiber with 

 sheaths; C, unipolar cell (such a cell may arise by modification of a bipolar cell as shown 

 in Fig. no); D, pyramidal cell (from cerebral cortex); a, axon; c, collateral; d, dendrites; 

 cb, cell body; m, medullary sheath; n, nucleus of cell of Schwann's sheath; r, node of 

 Ranvier; s, sheath of Schwann; t, telodendron. (From Kingsley.) 



A 



B 



Fig. 109. — Cell-bodies of neurons showing arrangement of neurofibrils. A, from 

 human spinal ganglion; two cut fragments of the neuraxon lie near the cell-body. B, 

 "giant pyramidal cell" from human cerebral cortex. Highly magnified, a, neuraxon. 

 (From Morris, Human Anatomy.) 



