NERVE TRUNKS 



67 



are grayer than the medullated nerves. The non-medullated fibers fre- 

 quently branch. 



It is worthy of note that in the fetus, at an early period of development, 

 all nerve fibers are non-medullated. 



"S- 



Ar. 



FIG. 88. Transverse Section of the Sciatic Nerve of a Cat, about X 100. It consists of bundles 

 (Funiculi) of nerve fibers ensheathed in a fibrous supporting capsule, epineurium, A; each bundle 

 has a special sheath (not sufficiently marked out from the epneurium in the figure) or perineurium, 

 B, the nerve fibers, N, f; L, lymph spaces; A r, artery; V, vein; F, fat. Somewhat diagrammatic. 

 (V. D. Harris.) 



Nerve Trunks. Each nerve trunk is composed of a variable num- 

 ber of different-sized bundles, juniculi, of nerve fibers which have a special 



FIG. 89. Small Branch of a Motor Nerve of the Frog, near its Termination, Showing Divis- 

 ions of the Fibers; a, into two; b, into three. X 350. (Kolliker.) 



