710 PLAGIOSTOMATA— SELACHOIDET. 



Family, I— CARCHARIIDtE. 



The snout may be produced longitudinally or laterally. Spiracles absent or present. Eye with a 

 nictitating membrane. A small pit may or may not exist above the root of the tail, and a groove at the 

 angle of the mouth may be present or absent. Mouth crescentic, inferior. Teeth may be erect or oblique, 

 with a single cusp, having smooth or serrated edges : or they may be small, the cusps being obsolete : or with 

 one in the centre and one or two lateral ones. The first dorsal fin, destitute of a spine, is placed opposite 

 the interspace between the pectoral and ventral : anal fin present. 



Sharks are found all along the coasts of India, but their carrying off human prey is not a common 

 occurrence. The most savage species appear to be the ground sharks of the rivers, as Carcharias Gangeticus, 

 which seldom loses an opportunity of attacking the bather. The Galeocerdo Raynpri, is likewise dreaded along 

 the coast or in the harbours. Though stationed several years at Cochin, I could only ascertain a single instance 

 of a living human being having been cawied oil' by these fishes. The most frecjuent accidents occun-ing are 

 after the tish has been hooked and lifted into the fisherman's boat : or else while entangled in a net when 

 attempts are made to seize it or cut it adrift. Corpses are almost immediately attacked by sharks. 



In some years they are much more numerous than in others, and this is due to the presence or absence 

 of shoals of smaller fish, as sardines (see Glupea loncjiceps, p. 637) . 



Sharks and rays are captured to a large extent both for the oil which is obtained from their livers, and 

 on account of the flesh of those of medium size, which is salted and sold to the poor.* Their fins likewise 

 are exported to China, where due to the gelatine contained in them, they are in request for making soups, 

 while the skins of some forms ai-e employed as shagreen for scabbards of swords. In most localities they are 

 captured by baits secured to a rough hook, which is attached to a chain : but ofE the coasts of Sind shark nets 

 of strong twine or string are used, and which are capable of holding these fishes at least ujj to 20 or 30 feet in 

 length {see p. 718). 



SYNOPSIS OF GENERA. 



First group — Caeciiaeiin,^. 

 Snout produced longitudinally. Teeth erect or oblique, with a single cusp, which has smooth or serrated edges. 



a. — A pit at the hase of caudal fin. 



1. Carcliarias. No spiracles, p. 710. 



2. Hemigaleus. Spiracles minute or small. Teeth serrated or notched in the upper jaw. Distinct 

 labial folds, p. 717. 



3. Galeocerdo. Spii-acles small Teeth serrated in both jaws. Caudal fin with a double notch, p. 718. 



Second group— Ztgj.niina. 



Head produced laterally into the shape of a hammer. Nostrils on front edge of head. Teeth oblique, with a 



single cusp, having sharp smooth edges. 



4. Zi/gaina. Spiracles absent, p. 719. 



Third group — Mustelina. 

 Teeth small, having a central and one or two smaller lateral cusps, or such may be obtuse. 



5. Triccnodon. No spiracles. A pit at the root of the caudal fin, p. 720. 



6. Mustelus. SpLracles small : labial folds well developed. Teeth obtuse. No pit at base of caudal fin. 



20. 



First group — Carchaeiina. 

 Snout produced longitudinally. Teeth erect or oblique, with a single cusp, which has smooth or serrated 



edges. 



a. — A pit at the base of caudal fi ii. 

 Genus, 1.— Carchaeias, Midler and Henle. 

 Scoliodon, Aprion or Aprinodon, Physodon, Hypoprion, Prionodon, Miiller and Henle: Prion ace, Cantor : 

 Eidamia, Isogomphodon, Lamiopsis, Platypodon, Hypoprionodon, Isopilagiodon and Cynocephalus, Gill. 



' The Seedees (Africans) in Bombay buy small ones as their usual food. 



