Histology 



317 



Fig. 258. 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. 260). (D) Pyramidal cell (from cerebral cortex), (a) Axon; 

 (c) collateral; (cb) cell-body; (d) dendrites; (m) medullary sheath; (n) nucleus of 

 cell of Schwann's sheath: (r) node of Ranvier; (s) sheath of Schwann; (/) telo- 

 dendron. (Courtesy, Kingsley: "Comparative Anatomy of Vertebrates," Phila- 

 delphia, The Blakiston Company.) 



Fig. 259. 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, (a) Neuraxon. (Highly 

 magnified.) (Courtesy, Jackson: "Morris' Human Anatomy," Philadelphia, The 

 Blakiston Company.) 



