108 THE PLAGIOSTOMIA. 



Physodon. 



Physodon MtiLLER & Henle, 1841, Plagios., p. 30. 



Body slender, compressed; head long, depressed, snout long. Teeth not 

 serrated, anterior raptorial, with long crooked cusps bent toward the angles of 

 the mouth; bases broad, somewhat swollen. A small median tooth on the upper 

 jaws and two small symphyseal teeth on the lower. Mouth with a short labial 

 fold. Pectorals short, subtruncate. First dorsal nearer to ventrals than to 

 pectorals. Anal much longer than second dorsal. 



India; China. 



Physodon mulleri. 



Carcharias (Physodon) mUlleri Muller & Henle, 1841, Plagios.. p. 30, p!. 19, f. 1 (teeth); Dumeril, 

 1865, Elasm., p. 347; Gunth., 1870, Cat. fishes Brit, mus., 8, p. 360. 



Elongate, slender, body cavity nearly half the total length. Head broader 

 than deep, snout long, broad, pointed, about one third of the length to the fifth 

 gill cleft. Nostrils at about one fifth of the length from the mouth forward, far 

 apart. Mouth greatly arched, little wider than long, with a short labial fold 

 in the angle and on the lower jaw. Teeth smooth on the edges, in §| rows; one 

 median tooth on the upper jaws, two symphyseal teeth on the lower; cusps of 

 .forward teeth long, sharp, resembling those of Isurus in outline, but more com- 

 pressed, with base wide and swollen and with a deep notch behind the cusp. 

 Eyes small, lateral, above the middle of the mouth, nictitating membrane ante- 

 rior. Gill clefts wider than the eye, equal, hindmost one above the edge of the 

 pectoral. Fins small. Pectorals subtruncate, inner angle about 90°. Origin 

 of first dorsal about midway between the bases of pectorals and ventrals, base 

 not reaching to a vertical from the origins of the ventrals, hind angle acute, 

 above the middle of the ventral. Second dorsal very small ; base less than one 

 third of either first dorsal or anal, extending little farther back than that of the 

 anal; hind angle acuminate. Base of anal distant its length from that of the 

 caudal or from the bases of the ventrals. Tail with a distinct pit in front of 

 the supracaudal. Caudals moderate, subcaudal lobe medium. Scales very 

 small, with three strong keels each of which is produced in a sharp point. Distal 

 end of clasper of male with four blades the third of which is smaller, short, 

 rounded, and toothed on the edge. 



Back brownish; below whitish; fins darker, except on the edges. 



Specimen described an adult male from China. Total length 17j, snout 

 to pores 8z, snout to fifth gill opening 3§, snout to mouth l| inches. 



