SHARKS. 123 



distended by a voluminous prey. Some of them are ovo-vivipa* 

 raws, and others lay eggs covered by a hard, horny shell. It is 

 divided into sharks, saw- fishes, rays, &c. 



9. The SHARKS, Sc/ualides, constitute a large tribe, recog- 

 nisable by their general form, which differs but little from that of 

 ordinary fishes. Their body is elongated, the tail stout and 

 fleshy, and the pectoral fins of moderate size. Their eyes are 

 situate as usual, on the sides of the head; their muzzle presents 

 nothing remarkable, and the openings of their branchiae are 

 found upon the sides of the neck ; the shoulder bones are 

 suspended in the flesh, without articulating either with the 

 cranium or vertebral column, and the skin is rough and their 

 flesh coriaceous. Most of them attain a large size, and are very 



1 voracious. 



10. The Roussettes, Set/Ilium, are distinguished from other 

 Squali, by a short, obtuse snout, by the nostrils being pierced 

 near the mouth, and surrounded by a groove which extends to 

 the lip. These fishes are provided with spiracles and an anal 

 fin ; their dorsals are behind it, and the caudal is elongated, not 

 forked and truncated at 'the end; their branchial openings are 

 situate partly under the pectorals. There are two large species 

 on the coast of France, the Great Roussette, or Sea- Dog, 

 Squalus canicula, (Fly. 62.) which is 



also found on the American coast, at- 

 tains three or four feet in length, and 

 the Rock- Shark, Squalus catulus. 

 The skin of these fishes, which is 

 studded with a multitude of small, 

 stony tubercles, becomes very rough SEA-DOG. 



on drying, and is then employed in the arts for polishing hard 

 bodies, such as ivory. 



11. Sharks properly so called have the nostrils without a 

 groove, and situate under the muzzle, which is prominent. The 

 caudal fin is more or less forked. Some of them have spiracles, 

 and in others they are wanting. 



12. The genus Carcharias, have no spiracles, and are pro- 

 vided with an anal fin ; their muzzle is depressed and the mouth 

 is strongly armed with pointed, trenchant teeth, which are gene- 

 rally dentate on the edges. 



9. What are the characters of Sharks ? 



10. How are Roussettes distinguished from other Sharks ? 



1 1 . How are Sharks properly so called characterised ? 



12. What are the characters of the genus Carcharias? 



