NERVE 



846 



NERVE 



White. A synonym of medullated nerve-fiber. See 

 N. -fiber. N-fibril, a very fine filament of nerve- 

 tissue entering into the formation of the axis-cylinder. 

 N.- force, the energy of the nervous system. See 

 Isomeric Theory of. N., Forty-fourth, the sympa- 

 thetic nerve. N., Frenator, an inhibitory nerve. N., 

 Frigorific, a sympathetic nerve, so-called because its 

 stimulation causes a fall of temperature ; the vaso-con- 

 strictor nerves are frigorific nerves. N., Ganglionic. 

 A synonym of N., Sympathetic. N. -grafting, the 



transplanting of a portion of healthy nerve from an 

 animal to man, after surgical operations necessitating 

 the removal of a portion of a nerve. N.-head, the 

 optic disc or papilla. N.-hill, N. -hillock, the motor 

 end-plate of a nerve. N., Incident. A synonym of 

 A r . , Afferent. N., Katabolic, one giving rise to chemic 

 and destructive changes in a muscle or other tissue. N., 

 Krause's Ulnar Collateral, a branch of the mus- 

 culo-spiral, which accompanies the ulnar nerve for 

 some distance and ends in the lower part of the inner 



ILLUSTRATIONS OF TYPICAL NERVE-STRUCTURES. 



tl 



a 



Multipolar Nerve-cell from the Spinal Cord. 

 z. Axis-cylinder process, y. Protoplasmic processes. 



Medullated Fiber, with 

 Schwann's Sheath. 



Rf.mak's Fibers. 



Nerve-fibers treated with silver nitrate and showing Froh- 



mann's lines. 



Medullated fiber, with 

 Schwann's sheath, c. Neu- 

 rilemma, t, t. Ranvier's 

 nodes, b. White substance 

 of Schwann, d. Cells of 

 the endoneurium. a. Axis- 

 cylinder. 



Transverse Section of a 

 Nerve-fiber. 



Primitive Fibrilla and 

 Axis-cylinder. 



Medullated Varicose 

 Fiber. 



Peripheral Ganglionic 

 Cell, with a Connec- 

 tive-tissue Capsule. 



Ganglionic Cki l, showing 

 a Spiral and a Straight 

 Process. 



