BULLETIN OV THE UNITED STATES FISH COMMISSION. 45 



white below. Fins all pale, the tip of anal and edges of caudal somewhat 

 dusky; female with fins rather darker, the upper edge of the pectorals 

 and ventrals largely black; in the male these fins are pale, or somewhat 

 brown above. Maxillary barbels blackish; lower pale. 



Generally abundant along the Pacific coast of tropical America. 

 Specimens were observed by Mr. Gilbert at Mazatlan, Libertad, Punta 

 Arenas, and Panama. It reaches a length of about 18 inches, and is 

 seldom eaten. 



The males of this species, according to Dr. Steindachner, cany the 

 eggs in their mouths until after hatching. 



11. Arius elatturus, sp. nov. (29408.) 



. Head 3f (4£); depth 5| (6|); width of head 4f; length (29408) 12£ 

 inches. D. I, 6 ; A. 4, 14. 



Body low, not very elongate, the head rather short and very broad, 

 much broader than deep, the snout depressed and very broadly rounded, 

 almost truncate. Eye moderate, placed rather high, its diameter 7 in 

 head. Jnterorbital space 2£ in head ; snout 3£ ; breadth of mouth If-. 

 Mouth large, with thickish lips, the upper jaw considerably project- 

 ing. Teeth on vomer and palatines villiform, but bluntly conical, less 

 acute than in most oi the species. Vomerine patches oblong, small, 

 separated by a narrow interspace from each other and from the palatine 

 bands, which are roundish and comparatively small, with a backward 

 prolongation. Teeth in the jaws in broad bands. Barbels rather short, 

 the maxillary barbels reaching a little past base of pectorals, the outer 

 mental barbels a little past gill-opening, the inner a little more than one- 

 third head. H 



Ante-dorsal shieM not very short, crescent-shaped, with a distinct 

 median keel, its length on the median line about one-third its breadth. 

 Occipital process short, broadly triangular, with concave sides which 

 spread out abruptly near the base, forming a sort of shoulder ; its length 

 scarcely equal to its width at base. Median keel well developed. 



Fontanelle broad and shallow, abruptly narrowed posteriorly at a 

 point a little nearer base of dorsal than tip of snout, but extending as 

 a groove to a point distant less than a diameter of the eye from the base 

 of the occipital process, this groove indistinct in the smaller specimen. 

 Greatest width of fontanelle scarcely more than half eye. Shields of 

 head granular-striate, the. roughness less coarse than in A. kessleri. 

 Interorbital space with two prominent ridges and numerous stria?, none 



