46 



EXPERIMENTAL PHYSIOLOGY 



XXVIII. — ^Nervous Tissue (Optional). 

 Apparatus. — Prepared slides of ganglion cells and nerve fibers, * 



compound microscope. 



Directions. — A. The Nerve 

 Cell, Note the irregular out- 



DendHtes. ^^^ ^f the Cell; the wavy pro- 

 jections, or dendrites; the rod- 



Nerve process jjj^^ projcctioiis, or Tierve proc- 

 esses. Note the position of the 

 nucleus. Has the cell one or 



Axis cylinder morc ncrvc proccsscs? Draw 

 and locate all parts, under the 



NeuHlemma high pOWCr. 



B. The Nerve Fiber. Make 

 out from your study of the 

 nerve fiber, the axis cylinder 

 in the center. (This corre- 

 sponds to the nerve process of 

 A.) Next outside this is the 

 medullary sheath, and on the 

 very outside the neurilemma. 

 Make a drawing showing all 

 these parts. For their relation 

 compare with Fig. 21. 



Terminal 

 branches 



Fig. 21. — Scheme of a Neuron: a, 

 free axis cylinder; 6, axis cylinder 



surrounded by neurilemma alone; 



c. axis cylinder surroimded by ^^ tisSUCS of the body CaU 



medullary sheath alone ; d, axis ^ ^ 



cylinder surrounded by the sheath bc plaCCd iu OnC of the aboVC 



se"gte2"X"ln^^^^^^^^ classcs— cpithcUal, connective, 



the nodes of Ranvier). mUSCUlar, Or ncrVOUS. 



^A smear preparation of spinal cord may be prepared as follows: Rub a 

 piece of fresh spinal cord in water between two cover glasses. Mount and 

 run under the cover glass a drop of methyl green. Both nerve fibers and 

 nerve cells appear in such a preparation. 



