122 THE PLAGIOSTOMIA. 



Hypopkion hemiodon. 



Carcharias (Hypoprion) hemiodon Muller & Henle, 1841, Plagios., p. 35, pi. 19, f. 2 (teeth); Dum^ril, 

 1865, Elasm., p. 351 ; Gunth., 1870, Cut. fishes Brit, mus., 8, p. 362; Day, 1878, Ind. Fishes, p. 714. 

 Hypopnonodo7i hemiodon GihJj, 1861, Ann. N. Y. lye., 7, p. 409 (nameonly). 



Snout moderate, blunt, much shorter than that of P. macloti. Nostrils 

 little smaller than the eyes, midway in the preoral length. Teeth in —^ rows; 

 upper subtriangular, shghtly oblique, smooth on the inner edge, notched on the 

 outer and bearing several blunt denticles on the basal portion; lower not ser- 

 rated, cusps narrower, on broad bases, nearly erect. A row of smaller median 

 teeth above and below. Distance between the outer angles of the nostrils equal 

 that between end of snout and mouth. Outer and inner angles of pectorals 

 rounded, hind margins concave. First dorsal close behind the pectoral, upper 

 angle rounded, hinder acuminate, hind margin indented. Second dorsal above 

 the anal, origin little behind that of the latter, base two thirds the length of the 

 anal base, upper angle blunt, hinder acuminate. Hind angle of anal acute, 

 hinder margin deeply notched. In teeth at hand the serrations on the outer 

 part of the base of the lower teeth are nearly as distinct as those on the bases of 

 the upper teeth. 



Blackish gray; lighter below. 



Pondicherry; India; Calcutta. . 



Hypoprion playfairii. 



Carcharias (Hypoprion) playfairii Gunther, 1870, Cat. fishes Brit, mus., 8, p. 362. 



Snout short, broadly rounded, preoral length two thirds of the width and 

 rather more than the length of the mouth; nostrils midway to the end. Teeth 

 erect, with narrowed cusps on broad two-rooted bases, in if rows; upper rather 

 wider than the lower, with obtuse denticulations on the bases. Orbits much 

 narrower than the gill openings. Pectorals moderate in length and width, not 

 reaching the end of the dorsal. Dorsal nearer to the bases of the pectorals than 

 to the ventrals. Second dorsal one third as large as the first, equal and exactly 

 opposite to the anal. Caudal one fourth of the total length. 



A black spot on the end of each of the fins. 



Zanzibar. 



Hypopijon signatus. 



Hypoprion signalus Poey, 1868, Repertorio, 2, p. 452, pi. 4, f. 7, 8; 1876, An. Soc. Esp. hist, nat., 6, 



p. 199; JoRD. & EvERM., 1896, Bull. 47, U. S. nat. mus., p. 41. 

 Hypoprion longirostris Poey, 1876, An. Soc. Esp. hist, nat., 5, p. 198, pi. 9, f. 8, 9, 



