XIV] NERVE FIBRES 111 



more distinctly the elongated nuclei attached to them 

 at short intervals. 



9. Tease out in dilute glycerine a small piece of 

 the cervical sympathetic nerve (osmic acid) of a cat 

 or rabbit. 



Note the numerous small medullated fibres ; some 

 non-medullated fibres may also be seen. Compare the 

 size of the medullated fibres here (most about 3/t in 

 diameter) and in the sciatic nerve ( 1). 



10. Peripheral Course of Nerves. In the 



specimen prepared Less. xm. 4 : observe 



a. Under a low power, the nerve running across 

 the lower part of the muscle and sending off fibres 

 or bundles of fibres at intervals and so spreading out 

 over it. 



6. Under a high power, that where the lateral 

 bundles (especially the smaller ones) are given off; one 

 or more of the nerve fibres divide into two fibres, the 

 division taking place at a node. Trace a small bundle 

 of nerve fibres, the nodes are very close together. Each 

 nerve fibre apparently ends abruptly over a muscle 

 fibre ; in this specimen it can only be traced as far as 

 the blackened medulla extends. 



11. Examine the gold chloride preparation (made 

 in Less. x. 7) of the cornea. Note 



a. The small separate bundles of nerve fibres enter- 

 ing the cornea at its periphery ; the medullated fibres on 

 account of their medulla are more deeply stained than 

 the non-medullated fibres. 



