BARRACUDAS, REMORAS AND OTHERS 179 



the jaws and strong, pointed teeth are equally developed on 

 both sides of the head. The dorsal fin forms a fringe along 

 the edge of the head and body, extending from above the eyes 

 nearly to the tail, and is supported by about 100 flexible rays. 

 The anal fin is similar, but starts farther back and has only 

 70 to 85 rays. The caudal fin is well developed, and is placed 

 at the end of a stout peduncle. The pectoral fins are unequal 

 in size, that of the eyed side being the larger. The pelvic fins 

 are small, about equal, and are placed below the hinder part 

 of the head. There is a distinct lateral line on each side of 

 the body, which is arched above the pectoral fin and from 

 thence runs straight to the tail, where it extends on to the 

 caudal fin. There is no air-bladder. The coloration of the 

 eyed side is nearly uniformly olive-brown, dark brown or 

 black, and that of the blind side is pearl-white ; young 

 individuals are usually marbled with paler and darker shades. 



Grow to a length of about 10 or 12 feet and a weight of at 

 least 500 lb. 



Only two species are known : the Common Halibut (H. 

 hippoglossus) , widely distributed in the North Atlantic ; and 

 the Pacific Halibut (H. stenolepis), from the North Pacific. 



The Halibut has a longer and generally plumper body than 

 the majority of Flatfishes, and its large mouth is armed with 

 rows of strong, pointed teeth. In these respects it presents a 

 very different appearance to, say, the Plaice, which has a shorter, 

 deeper and thinner body, and a smaller mouth, which is twisted 

 over towards the blind side of the head, so that both the jaws 

 and the teeth are much better developed on that side. These 

 differences in structure are related to differences in the habits 

 of the two fishes. The Halibut sometimes lies in wait for its 

 prey, lying fiat on the sea bottom, but, as its form suggests, 

 it is a powerful swimmer, and quite often goes in active pursuit 

 of other fishes, sometimes chasing them right up to the surface. 

 The Plaice, on the other hand, like the great majority of 

 Flatfishes, is much less active, spends practically all its time 

 on the bottom, and feeds on shellfish, crustaceans, worms, and 

 other ground-living creatures. When the Halibut is chasing 

 its prey it gets along mainly by the aid of its strong muscular 

 body and powerful tail, but the Plaice relies more upon wave- 

 like movements of the body and of the fringing fins to glide 



