SHARKS 35 



of the anal, which just reaches the caudal. The caudal fin is 

 very long, with a straight axis, and with a notch in the hinder 

 part of the lower lobe. The pectoral fins are broad. The 

 general coloration is yellowish-brown, ornamented with many 

 vertical series of rounded dark spots ; the young have a 

 very different pattern, with broad dark brown cross-bars 

 with black edges, separated from one another by narrower 

 interspaces of pale yellow. As the fish grows up the bars 

 gradually become paler and dark spots appear on them, 

 while the dark edges of the cross-bars break up into spots. 



Grows to a length of 6 feet or more. 



The single existing species (5. tigrinum) is widely distributed 

 in the tropical parts of the Indian Ocean, East Indian Archi- 

 pelago, and Chinese Seas, and occasionally strays southwards 

 to the coasts of Australia. 



This handsome shore-dwelling Shark is quite harmless, 

 and feeds mainly upon shellfish and crustaceans. Little is 

 known of its habits. It produces eggs, that are deposited 

 close to the shore. Apart from the use of its skin as shagreen, 

 it has little economic value. 



REQUIN SHARKS. 



(Family Carcharinid.e.) 



Sharks with a long body and somewhat flattened tail. 

 The snout is more or less pointed, flattened above, and projects 

 above the crescent-like mouth. The eyes are each provided 

 with a third eyelid, or nictitating membrane, that can be 

 drawn up across the eye from below. There are no grooves 

 connecting the mouth with the nostrils. The spiracles are 

 small or absent altogether. The last i or 2 external gill-clefts 

 on each side are above the base of the pectoral fin. There 

 are two dorsal fins, without spines, the first of which is usually 

 placed in front of the pelvic fins ; there is a single anal fin. 



This is the largest family of existing Sharks, and its members 

 are found nearly all over the world. The family is a compara- 

 tively modern one, as fossil remains, mostly teeth, do not 

 occur in rocks older than those of the Eocene period. All 

 the Requin Sharks are viviparous or ovo-viviparous. 



