126 THE PLAGIOSTOMIA. 



upper teeth narrow, lower narrower, lanceolate 



pectorals broad ellioti (page 142) 



upper teeth broad, triangular, lower narrow 



pectorals little longer than wide . . iemminckii (page 142) 

 snout long; pointed; origin of second dorsal forward of anal 

 upper teeth like the lower, narrow, erect 



pectorals large, two thirds as broad as long oxyrhynchus (page 143) 

 snout moderate, blunt ; second dorsal origin opposite the anal origin 

 upper teeth broad, triangular, lower narrower 



pectorals longer than broad . . . munsing (page 144) 

 snout very short, blunt; second dorsal origin behind anal base 

 upper and lower teeth triangular, smooth 



pectorals elongate ..... maou (page 144) 



Carcharinus platyodon. 

 Plate 3, fig. 4-6. 



Squalus platyodon Poey, 1861, Memorias Cuba, 2, p. 336, pi. 19, f. 5, 6. 



Squalus obtusus Poey, 1861, ibid., p. 337, pi. 19, f. 7, 8. 



Eulamia obtusa Poey, 1868, Repertorio, 2, p. 447, pi. 4, f. 1, 2; 1876, An. Soc. Esp. hist, nat., 5, p. 189. 



Carcharias platyodon Jord.\n & Gilbert, 1882, Proc. U. S. nat. mus., 5, p. 243; 1883, Bull. 16, U. S. 



nat. mus., p. 872, 967. 

 Carcharinus platyodon Jord. & Everm., 1896, Bull. 47, U. S. nat. mus., p. 39. 



Head broad, convex. Snout depressed short, broadly rounded in front, in 

 length equal to width of mouth. Nostrils about midway from mouth to end of 

 snout; width of internarial space less than length of snout and greater than 

 length of mouth. Mouth wide, greatly arched forward, with a very short labial 

 fold visible on the upper jaw at the angle of the mouth. Teeth serrated, com- 

 pressed, nearly erect, in §1 rows; one to three very small hooked teeth at the 

 sj'^mphyseal between the larger ones; upper teeth broad triangular, with a 

 shallow concavity on the inner margin and a trifle more pronounced one on the 

 more acuminate cusps; lower more erect, with narrower outer edge near the base. 

 Eye moderate, nictitating membrane well developed. Gill openings narrow, as 

 wide as the eye, hindmost two above the pectoral. Outer angles of all the fins 

 rounded. Pectoral larger than the first dorsal, inner angle reaching beyond a 

 vertical from the origin of the first dorsal. First dorsal large, nearer to bases of 

 pectorals than to ventrals, origin little in front of inner angle of pectoral. Inter- 

 dorsal space less than length of head. Hinder angles of dorsals and anal acute. 

 Second dorsal very small, origin behind extreme ends of ventrals, in front of 



