CII. VII.] 



NERVE-FIBRES 



93 



Staining with silver nitrate produces a peculiar appearance at the 

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



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



FIG. 121. Several fibres of a bundle of medullated nerve-fibres acted upon by silver nitrate to show 

 behaviour of nodes of Ranvier, M, 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.) 



substance which occurs between the segments of the neurilemma ; the 

 other limb of the cross is due to the staining of a number of minute 



Ar. 



FIG. 122. Transverse section of the sciatic nerve of a cat about x 100. It consists of bundles 

 (funiculi) of nerve-fibres ensheathed in a fibrous supporting capsule, epineurium, A ; each bundle 

 has a special sheath (not sufficiently marked out from the epineurium 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.) 



transverse bands in the axis cylinder (Fromann's lines), which is here 

 not closely invested by the medullary sheath (fig. 121). 



