PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 243 



3. Carcharias platyodon (Poey.) J. & G. Shoirl-tiostd SJmrk (Galveston). 

 ^Squalm2)laUiodon Poey, Memorial, Cuba, II, 331. 

 ISqualus obtu-siis Poey, Memorias, Cuba, II, 337. 

 lEidamia obtusa, Poey, Eep. Pis. Nat. Cuba, 1868, 447. 



This is the commonest of the large sharks found on the coast of Texas 

 in the summer. A young male specimen 32 inches long was obtained 

 at Galveston, and the jaws of a verj^ large example, in the possession of 

 Mr. E. Gabriel, of Galveston, were also examined. 



The following is a description of the specimen obtained: 



Color slaty, with a distinctly bluish tinge above, whiter below, the 

 white extending higher posteriorly, and forming a faint lateral stripe. 

 Caudal fin all blackish; second dorsal and anal tipped with dusky. 



Body comparatively short and stout. Head very short, broad, bluntly 

 rounded anteriorly, and much depressed. Mouth very broad and short. 

 Length of snout from mouth If in distance between angles of mouth. 

 Breadth of mouth between angles twice length of mouth. Angle of 

 mouth with a pit from which radiate two very short furrows. 



Inner edge of nostril with a very blunt lobe. Distance between nos- 

 trils but a trifle less than length of snout from mouth. Length of 

 nostril greater than eye and half its distance from eye. Eye slightly 

 nearer nostril than angle of mouth. Kostril a little nearer eye than tip 

 of snout. Distance from eye to snout 1| times in interorbital width, 

 which is 1§ in length of head to first gill opening. Gill openings short, 

 the height of one a little more than half length of gill area. Top of 

 head with numerous mucous pores. 



First dorsal beginning close behind pectoral, at a distance from the 

 posterior root of the latter equal to about U diameter of the eye; the 

 fin moderate in size, its anterior lobe rather obtuse, the posterior little 

 produced ; the free edge of the tin little concave. Anterior lobe extend- 

 ing when depressed a little beyond posterior lobe; the fin a little 

 higher than long, its base 2J times in the interspace between dorsals, 

 and about equal to the distance from the posterior base of the first dor- 

 sal and tlie vertical from the insertion of the ventrals. Length of pos- 

 terior lobe two-fifths base of the fin. 



Second dorsal very small, its base 5 times in the interspace between 

 dorsals, less than half base of first dorsal ; the fin scarcely as long as 

 high ; its posterior lobe moderately produced. 



Caudal moderate, the lower lobe not falcate, 2^ times in the length 

 of the upper lobe; the latter 3| in the total length, about equal to the 

 distance from the snout to the base of the dorsal. 



Anal a little larger than second dorsal and placed a little further 

 back; its lobes more falcate, its distance from base of caudal 1 J its 

 base. 



Ventrals moderate, their lobes bluntish, the anterior margin scarcely 

 more than half the length of the base. Pectorals rather small, their 

 tips not falcate, reaching slightly past posterior part of dorsal ; their 

 free margins a little concave, the anterior margin a little shorter than 



