XV111 



MUSCULAR AND NERVOUS SYSTEMS. 



MUSCULAR SYSTEM. 



The chief masses of muscular structure in this class of animals are seen 

 the great lateral muscles of the body, generally four in number in teleosteans, 

 and which are arranged longitudinally, but divided by oblique tendinous 

 bands (fig. 5) of a gelatinous character (and which dissolve on boiling) into 



Wz? 



Fig. 4. Internal Organs or Carp. 

 br, branchiae or gills ; c, heart ; /, liver ; vn, vn', swimming bladder ; ci, intestinal tract ; 

 o, ovaries ; u, urethra ; ,vent; o, oviduct. 



numerous flakes or semi-conical masses termed myocommas. These four 

 longitudinal layers of muscles have the tendinous bands directed much as 

 follows : the upper series passing downwards and backwards, the succeeding 

 layer downwards and forwards, the third downwards and backwards, and 

 the lowest downwards and forwards. These flakes are arched backwards, 

 being convex anteriorly. The number of tendinous intersecting bands 

 correspond with the vertebras into which they are inserted. The various 

 modifications observed in these muscles, and the systems employed for the 

 movement of the fins, the jaws, eyes, breathing, &c, it is unnecessary to 

 enumerate in this place. 



NERVOUS SYSTEM. 



This is subject to very great variation, and the brain, which does hot fill 

 the cranial cavity in adults, is comparatively small in proportion to that of 

 the general mass of the body. 



