. Elements of histology. Histology. 146 Eleisients of Histology. 143. The neurilemma presents at certain definite intervals annular constrictions—the nodes or constric- tions of Rani-ier (Figs 99, 100, 101)—and at these nodes of Ranvier the medullary sheath, but not the axis cylinder and its special sheath, is suddenly inter- rupted, and sharply terminates at the constriction. The neurilemma is at the same time thickened by annular permanent, folds (see b in Fig. 101). The portion of the nerve fibre situated between two nodes is the internodal segment. Each in- ternodal seojment has orenerallv
. Elements of histology. Histology. 146 Eleisients of Histology. 143. The neurilemma presents at certain definite intervals annular constrictions—the nodes or constric- tions of Rani-ier (Figs 99, 100, 101)—and at these nodes of Ranvier the medullary sheath, but not the axis cylinder and its special sheath, is suddenly inter- rupted, and sharply terminates at the constriction. The neurilemma is at the same time thickened by annular permanent, folds (see b in Fig. 101). The portion of the nerve fibre situated between two nodes is the internodal segment. Each in- ternodal seojment has orenerallv one, occasionally more than one, nerve corpuscle. The medullary cylinder of each internodal segment is made up of a number of conical sections (Fio-. 101, A) imbricated at their ends ¥W 99. -Two Nerve - ^ . Fibre's, showing the (Schmidt, Lantermann; and each such section is again made uj) of a large number of rod-like structures (Fig. 102) placed vertically on the been dissolved axis cvlinder (MacCarthy). away. The deeply- „ - , ^ 1 ihese rods are, however, con- nected into a network. The net- work itself is verv likelv the neuro- keratin of Ewald and Kiihne, where- as the interstitial substance of the network is probably the fatty substance leaving the nerve fibre in the shape of myeline droplets, when pres- sure or reagents are applied to the fresh nerve fibre. 144. Medullated nerve fibres without any neuri- lemma, and consequently without any nodes of Ranvier, with a thick more or less distinctly laminated medullary sheath, form the entire white substance of nodes or constric tions of Ranvier and the axis cy- linder. The me- dullary sheath has stained oblong nuclei indicate the ner\'e corpuscles within the neuri- lemma. (Atlas.). Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Klein, E. (Edward),
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