100 



NERVE. 



[CH. VII. 



Staining with silver nitrate produces a peculiar appearance at 

 the nodes, forming what is known as the crosses of Ranvier. 



One limb of the cross is produced by the dark staining of 



Fig. i2i. Several fibres of a bundle of medullated nerve-fibres acted upon 

 by silver nitrate to show peculiar behaviour of nodes of Ranvier, N, 

 towards this reagent. The silver has penetrated at the nodes, and 

 has stained the axis-cylinder, M, for a short distance. 8, the white 

 substance. (Klein and Noble Smith.) 



cement substance which occurs between the segments of the 

 neurilemma ; the other limb of the cross is due to the staining of 



N/, 



Ar. 



Fig. 122. Transverse section of the sciatic nerve of a cat about X 100. It consists of 

 bundles (fuuiculi) of nerve-fibres ensheathed in a fibrous supporting capsule, epi- 

 iieurium, A ; each bundle has a special sheath (not sufficiently marked out from the 

 epineunum in the figure) or perineurium'B ; the nerve-fibres N/are separated from one 

 another by endoneurium ; L, lymph spaces ; Ar, artery ; V, vein ; F, fat. Somewhat 

 diagrammatic. (V. D. Harris.) 



