PISCES FISHES. 489 



With such inferiority in their powers of communication with 

 the external world, and with faculties so circumscribed, we might 

 justly infer that, as relates to their intellectual powers, fishes hold 

 a position equally debased and degraded. Destitute of the means 

 of social intercourse, deprived of all sympathy even with indivi- 

 duals of their own species, friendless and mateless, the fish is 

 denied even the privileges of sexual attachment ; the female for the 

 most part ejects her countless eggs into the sea, heedless of the 

 male that blindly fecundates them as she is careless of the progeny 

 to which they give birth : thus, to pursue and destroy their prey 

 constitutes their chief enjoyment during life, and to be devoured 

 at last is the great end of their existence. 



(522.) We shall commence our account of the anatomy of fishes 

 by an examination of the internal skeleton which forms the frame- 

 work of their bodies. The reader has already seen in the CEPHA- 

 LOPODA the first appearance of an osseous system in the carti- 

 laginous pieces described in the last chapter, and will neces- 

 sarily expect that between the rudimental condition which cha- 

 racterizes the cephalic ring of the Cuttle-fish, and the complete 

 and perfect skeleton of the fish, various gradations of developement 

 will occur as we advance progressively from lower to more elevated 

 forms of the finny race. Nor in this will he be deceived. The 

 lowest tribes of fish possess a skeleton but little superior in its 

 organization to that of the Cephalopod : in the Myxine and 

 Lamprey the cranium is still cartilaginous ; and even the spinal 

 column, not yet divided into vertebrae, resembles a cartilaginous 

 cord extending from the head to the tail. Even in the Sturgeon, 

 the Skate, and the Shark, the skeleton is but very partially ossi- 

 fied ; and thus we are gradually and almost imperceptibly conducted 

 to the strong and bony framework of the typical fishes. 



(528.) Even in tracing the modifications observable in the 

 construction of the vertebral column, we have a beautiful illus- 

 tration of the progressive advances of ossification in this the 

 central portion of the osseous system. The spine of the Lam- 

 prey, although at first sight apparently entirely soft and cartila- 

 ginous, presents already in the arches which compose the spinal 

 canal, and in the soft cord that represents the bodies of the ver- 

 tebrse, slight indications of an incipient division into distinct 

 pieces : rings of ossific matter are distinguishable, encircling at 

 intervals the soft spinal cartilage upon which they perceptibly 

 encroach, so that on making a longitudinal section of the cord it 



