THE LOWER FISHES 



161 



Fig. 70. Monkfish. 



Distribution: Summer visitor to mid-Atlantic states. Most common near 

 Chesapeake, south to the Gulf of Mexico and the Caribbean. Not really plentiful 

 anywhere. 



Identification: Blue to ash-gray above with spots and mottled pattern. May 

 have some reddish tints. 



Habits: In summer, this is mainly an inshore fish. It lies on the bottom and 

 may pardy cover itself with sand or mud as rays are wont to do. From this van- 

 tage, it ambushes flatfish, skates, mullet, and other fishes. It also eats crustaceans 



O ' 7 7/ 



and molluscs, which it crushes with its strong jaws. In winter it strays to water 

 as deep as 700 fathoms. The young are born in early summer inshore in num- 

 bers up to twentv-five at a time. This shark has powerful jaws and may inflict 

 a painful bite if molested. The teeth are small and numerous. The term 

 "angel shark" refers to the angel-wing shape of the pectorals. 



Similar Species: The California angel shark, Squatina californica, is of similar 

 size to the Atlantic forms. It is found from Alaska to southern California and 

 is rather common in the south. The European monkfish, Squatina squatina, 

 gets much larger, 8 feet and 170 pounds, and is very plentiful in Europe. 



Rays: Order Hypotremata {"openings beneath") 



Among the most remarkable of the animals of the sea are the rays, sometimes 

 grouped as the order Batoidei. Most of them are greatly flattened, but just as 

 there are raylike sharks, there are also sharklike rays, so body form is not dis- 

 tinctive. The significant characteristics are ( 1 ) the enlargement and continuation 

 of the pectoral fins onto the head, (2) the position of the five pairs of gill slits 

 on the underside (forced there by the overgrowth of the pectorals), and (3) 

 the absence of lower and usually also of upper eyelids. 



The rays probably developed from squaloid sharks in response to the develop- 

 ment of expanded pectoral fins for greater mobility. The evolution of the ad- 

 vanced rays (Myliobatoidea) from the primitive types (Pristoidea) was the 

 result of the following steps: (1) the pectorals took over all locomotion, (2) 

 dorsal and caudal fins were lost, (3) the body became flat, (4) the enlarged 

 spiracles and eyes were moved to the top of the head, and (5) the tail became 



