130 FISHES FROM GUAYMAS — EVERMANN AND JENKINS. 



4. Scoliodon loiigurio Jordan & Gilbert. 



Tiburon. 



CarcharUis loiiffurio Jordan & Gilbert, Proc. U. S. Nat. Mns. 188)1, 106. (Mazatlan.) 

 iw/(o;Zw« ?o?i</urJo, Jordan & Gilbert, Bull. U. S. Fish Comiu. I(f8i, 105. {Mazatlan. 



Name only.) 

 Ciircharhinus lovgurio, Jordan, Proc. U. S. Nat. Mas. 1885, 363. (Name only.) 

 Jordan, Cat. Fishes N. A., 1885, 8. 



Two specimens, 17 aud 18 inches long respectively, were taken. 



5. Rhiiioptera steindachneri sp. nov. 

 (Type No. 43235, U. S. N. M.) 

 Gabilan. 

 (Plate I.) 



Widtb of disk 1.8 times its length; anterior border nearly straight 

 from spiracle for about two-thirds its length; thence to the tip slightly 

 convex, thus giving the fin the outline of a wing; posterior border 

 strongly concave in its outer half, nearly straight along its inuer half. 

 Length of anterior margin of pectoral not quite equal to the length of 

 the disk, but about equal to that of the posterior border; inner border 

 of pectoral more than half interorbital si)ace ; greatest width of ventral 

 fins equals half the interorbital width, while its length is nine-tenths of 

 the same. 



Tail very slender, its length greater than that of the disk (IJ times 

 length of disk in one specimen, while in the other it but slightly exceeds 

 the disk). 



Muzzle emarginate ; interorbital space concave, its width equal to the 

 distance between tlie S[)iracles, or the greatest depth of the body. The 

 cephalic fin is a little broader than the head, aud the length of the free 

 portion is contained more than twice in the interorbital width. 



Height of the dorsal fin 1^ times its length. In one specimen there 

 are two stout, strongly serrated spines near the base of the tail, these 

 lying very close together, while in the other specimen there is but one 

 spine; these spines are about equal in size, the length of the free por- 

 tion being about 1*.^ times that of eye. 



Skin everywhere smooth. 



Nasal valves continent into a broad flap with a free margin which, 

 together with the upi)er side, is covered with papilhe. 



Teeth in the lower jaw in seven series; seven teeth developed in the 

 median, and six in each of the other, series. The teeth of the median 

 series are hexagonal in shajie, the length being three-elevenths of the 

 breadth, which is nearly twice the breadth of a tooth of the second 

 series ; the teeth of the second series hexagonal, the length being seven- 

 twelfths of the width, which is again nearly twice the width of those of 

 the next series ; in the next series the teeth are diamond-shaped, the 

 length If times the breadth ; those of the last (outer) series triangular, 

 the length being about twice the breadth. 



