Quain's elements of anatomy . he ramified processes of the multi- Fig. 158. — Ramified nerve-cell FR05I ANTERIOR CORNU OF SPINAL CORD OF MAN (froin Grerlach). a, axis-cylinder process. 6, clumpof pigment gi-anules. Above the cellis seen part of the network of fibrilsmentioned in the text. polar cells lose themselves inthis network, and on the otherhand that some of the nerve-fibres may take origin fiomthe same general network. Sothat there would be in thisway through the intermediatesubstance of the grey matter ageneral connection, not onlyof the nerve-ceUs, but throughthese and their axis-cyl
Quain's elements of anatomy . he ramified processes of the multi- Fig. 158. — Ramified nerve-cell FR05I ANTERIOR CORNU OF SPINAL CORD OF MAN (froin Grerlach). a, axis-cylinder process. 6, clumpof pigment gi-anules. Above the cellis seen part of the network of fibrilsmentioned in the text. polar cells lose themselves inthis network, and on the otherhand that some of the nerve-fibres may take origin fiomthe same general network. Sothat there would be in thisway through the intermediatesubstance of the grey matter ageneral connection, not onlyof the nerve-ceUs, but throughthese and their axis-cylinderprocesses also of the nerve-fibres of the cerebro-spinalsystem. The fibres of origin of anerve on quitting the brain orspinal cord are in most casescollected into funiculi andacquire the connective tissue-sheaths above described. Thesesheaths are in continuity withthe membranes investing thebrain and spinal cord, and theirrelations will be better under-stood after the membranes inquestion have been described. Fig. Termiis^ation, or Peripheral Distribution, of Nerves. It may be stated, generally, and apart from what may apply to specialmodes of termination, that, in approaching their final distribution, thefibres,_ medullated and non-medullated, usually divide into branches,the division in the case of medullated fibres always occun-ing in thesituation of a node of Ranvier (fig. ). The axis-cylinder participatesin the division ; and since the white fibres frequently lose their medullarysheath shortly before they terminate, they are then represented by the 160 NEEVOUS SYSTEM. axis-cylinder and its ramifications, altliougli the primitive sheath maycontinne some little way along the branches after the medullary sheathhas ceased. By repeated division the fibres become smaller and smaller ;but whilst some of the resulting- small fibres may be simple, many arereally bundles of exquisitely fine fibrils. The fibres bear nuclei, which probably appertain to the prolongatio
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