MODE OF TERMINATION OF MOTOR NERVES IN ARTICULATA. 207 



may then be observed that the middle portions of the muscular 

 fibres, at all points of their circumference, present rows of fun- 

 nel-shaped processes forming little eminences of various size, 

 the apices of which correspond to the points of entrance of the 

 several branches of nerves. The latter appear in all instances to 

 consist only of a single axial fibril or axis cylinder; but this may 

 usually be seen to divide into two strongly diverging branches 

 immediately beneath the apex of the nerve cone or eminence, 

 and it may also be followed for a short distance into the 

 interior of the eminence. 



Fig. 34. 



Fig. 34. Muscular fibre, with the extremities of two nerves, from tlie 

 Hydrophilus piceus. 



At the termination of the nerve the medullary layer, which 

 has previously become extremely pale, entirely disappears; 

 the image of the sheath of the nerve, therefore, where it 

 joins the muscle, is not in the slightest degree obscured. It is 

 impossible for the observer who sees this to doubt that the nerve 

 sheath becomes continuous with the sarcolemma, and that the 

 contour of the latter, as it rises towards the cone, or extends 

 over the eminence, is directly continuous with the nerve sheath; 

 or, in other words, that the nerve sheath and the sarcolemma 

 form two communicating tubes. In whatever mode the nerve 

 terminations may be presented to the eye, whether in a 

 transverse section of the muscular fibre, or in the optic 

 transverse section which is seen if a bent muscular fibre pre- 

 sents its convexity to the observer, he will still be constantly 



