FISH IN GENERAL. G7 



divisible into three bands lengthways. The upper appears 

 to be the spinous dorsal ; the middle, the long dorsal, repre- 

 senting that which in tailed mammifera is the lateral lumbo- 

 sub-caudal; and the lower, the inferior lumbo-sub -caudal, 

 together with the abdominal muscles. Upon the middle 

 band is perceived a slight groove, containing mucous vessels, 

 but it is not of any depth. Tn the flat or depressed genera of 

 fish, these bands are horizontal, and parallel to each other. 

 Towards the tail, the great lateral muscles form an aponeu- 

 rosis, terminating in the shape of tendinous slips at the rays 

 of the caudal fin ; the whole apparatus producing flexibility 

 in a lateral and multifarious direction. 



Between the great laterals, on the back, and often also 

 below, there are two slender muscles, attaching to the bases 

 of the dorsals and anal, giving them motion, and to the fish 

 a power of bending upwards or downwards, as much as its 

 vertebras will permit. In the tail are three kinds of muscles ; 

 some superficial, in the form of a fan, implanted on the 

 aponeurosis of the great lateral ; others passing from one ray 

 to another, and placed between them ; and deep muscles 

 beneath both those, adhering to the end of the spine, and in 

 particular to the triangularly compressed vertebrae, which 

 forms its termination. The muscles proper to the dorsals and 

 anal fin being uniformly disposed, are six in number to each 

 ray, four deep and two superficial ; the latter inserted one on 

 each side, at the basis of the ray, and stretched transversely 

 across the great laterals, adhere to the skin ; the former 

 almost entirely hid between the two great muscles of the body, 

 are disposed so as to raise or depress the fin. Of the muscles 

 of the shoulder, independent of the great laterals, there is often 

 one passing from the lateral posterior part of the cranium to 

 the anterior superior part of the humeral bone, affording a 

 covering to the membrane which serves as diaphragm between 

 the cavity of the gills and the general cavity of the body. The 



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