TO THE ELEMENTAET EEBEES OE STEIPED MUSCLE. 
615 
I should state that the nerves and vessels may be stripped off the elementary fibre 
without difficulty. In this process the corpuscles external to the sarcolemma and in 
connexion with the nerves and capillaries are also removed. In the frog, the corpuscles 
which are so numerous amongst the fibrillae remain, but in the delicate muscles of the 
mouse I have often observed that all traces of corpuscles are completely removed by this 
operation, there being, at least in many instances, none within the sarcolemma. From 
numerous observations I have come to the conclusion that the nerves, like the capilla- 
ries, always ramify only upon the outer surface of the sarcolemma, and do not penetrate 
this structure *. 
Of the Manner in which Nerves terminate. 
From the arrangements above referred to, it would appear that the nerves may be 
described as originating in a network, formed by the oval corpuscles being connected 
together by intermediate fibres. This network is in close relation with other elements 
of the tissue to which the nerves are distributed. The nerves grow as the adjacent 
textures grow ; and in any form of fibrous tissue which has attained a certain degree of 
thickness, it is very difficult to demonstrate the delicate nerve-fibres running amongst 
the coarse fibres which interlace in all directions. They may, however, be traced out by 
the direction which the oval nuclei are seen to takef. The network is continually 
undergoing alterations by the formation of new nuclei and connecting fibres, and by the 
removal of old ones. From the connexion of this network with the nerve-fibres, it would 
seem to follow that an impression made upon a given portion of a sentient surface might 
be transmitted to the nervous centre by contiguous fibres, as well as by the one which 
would form, so to say, the shortest route ; and it is possible that impulses to motion may 
be conveyed to muscular fibres by a more or less circuitous path, as well as by a direct 
one. 
Of the so-called Tubular Membrane. 
Nerve-fibres are imbedded in a clear transparent material, which completely surrounds 
large separate fibres, in the form of a membrane, as usually described (the tubular mem- 
brane of authors). In the finer divisions, however, several separate nerve-fibres, differing 
much in thickness, are enclosed in this structure, and when examined by a moderately 
high power (220 diameters), appear to form one fibre. Many such fibres, which seem 
to consist of a single fibre, in good specimens may be resolved by a twelfth (700 dia- 
meters) into two, three or more fibres. 
Not unfrequently very narrow fibres may be traced for a long distance running close 
to an ordinary fibre imbedded in what would be called tubular membrane. I have seen 
* It is probable that tbe nerves and capillaries are very intimately connected witb the sarcolemma, and 
in some preparations one is almost led to conclude that the sarcolemma is itself composed of nerves, capil- 
laries, and a small quantity of fibrous tissue connecting them. 
t The determination of the connexions of the numerous nuclei is, as would be supposed, a very difficult 
matter. This difficulty, however, is greatly diminished by examining well-injected preparations, in which 
the nuclei connected with the capillaries can be easily distinguished from those belonging to the nerves. 
