80 SQUALIDES. 



ORDER II. CELACHII. 



SQUALIDES. 



SHARKS have no bones like those of the second 

 class of fishes ; they are elastic, cartilaginous por- 

 tions, embraced by numerous muscles. The bran- 

 chiae are pectinated, the openings quite numer- 

 ous, without gill covers, and the palate and post- 

 mandibulary bones are studded with teeth. They 

 have pectoral and ventral fins, but the last is 

 placed backwards, on the abdomen. While some 

 are viviparous, others are oviparous, and all the 

 males may be identified by appendages at the in- 

 ternal margin of the ventral fins. Though these 

 are the indications of the sex, their use is totally 

 unknown. 



GEN. SCYLLIAM. 



SEA-DOG, SCYLLIUM CANICULA, le chein de 

 mer, of which we have a well preserved specimen, 

 four feet in length. It follows the perch, when they 

 first make their appearance in the spring, in the 

 margin of deep water. It has a remarkable metal- 

 lic color, like crude antimony. The teeth are ve- 

 ry small, giving the sensation to the finger of a 

 coarse rasp ; its body is slender, the head flat, 

 the nose long and pointed : the eyes much re- 



