310 BULLETIN 189, UNITED STATES NATIONAL MUSEUM 

 NEBRIS OCCIDENTALIS VaUIant 



Nebris occidentalis Vaillant, 1897, p. 124, Pacific coast of Central America 

 (original description). — Meek and Hildebrand, 1925, p. 681, Panama Bay 

 (synonymy; description; range). 



Head 2.8 to 3.7; depth 4.0 to 4.8; D. VIII or IX-I, 28 or 29; A. II, 

 11 or 12; P. 19 or 20; scales about 100 to 116 (too small and uneven 

 to enumerate accurately). 



Body elongate, tapering sharply posteriorly, somewhat compressed; 

 back rather broad, little elevated; head rather low, somewhat com- 

 pressed (more so in small specimens than in large ones); caudal 

 slender, 3.7 to 5.7 in head; snout 3.5 to 3.6; eye 8.5 to 10; interorbital 

 3.0 to 3.33; mouth large, very strongly oblique; lower jaw projecting; 

 maxillary reaching to or somewhat past middle of eye, 2.1 to 2.2 in 

 head; teeth small, in a band laterally in upper jaw, reduced to 1 or 2 

 series anteriorly, widely separated medianly, those of lower jaw 

 principally in two irregular series; preopercle with a slightly crenulate, 

 membranous border; gill rakers at angle fully as long as eye, 13 or 14 

 on lower and 6 or 7 on upper limb of first arch; lateral line not arched, 

 becoming horizontal about over origin of anal; scales small, cycloid, 

 those on head larger than the ones on body, many of the scales in 

 lateral line Vvdth accessory scales, densely covering all the fins; dorsal 

 fins connected by membrane, at least m young, the spines very weak, 

 flexible, the third and fourth of about equal length, about 2.75 in 

 head; second dorsal highest anteriorly, its longest rays somewhat 

 shorter than the longest spines; caudal lanceolate, especially m small 

 specimens, the middle rays as long as head in young, proportionately 

 much shorter in large examples; anal small, the spines very weak; 

 ventral inserted under or slightly in advance of pectoral, 1.6 to 1.75 

 in head; pectoral very large, reaching far beyond tip of ventral, some- 

 what damaged, about 1.25 in head, and 4.5 in length. 



Color grayish brown above; silvery below; fins mostly more or less 

 olivaceous; first dorsal distally dusky; second dorsal with a somewhat 

 dusky margin; caudal, pectoral, and sometimes ventral dusky toward 

 tips. 



Six specimens, consisting of one large one, 395 mm. (330 mm. to 

 base of caudal) long, and five small ones 135 to 190 mm. (102 to 150 

 mm. to base of caudal) long, were secured by the Mission in the Gulf 

 of Guayaquil, off Puerto Pizarro; all taken m an otter trawl. Most 

 of the specimens are not in good condition. They were compared 

 with material from Panama Bay with which they are in agreement. 

 The head and body are more compressed in the yoimg, the caudal 

 peduncle is slenderer, and the caudal fin is longer and more strongly 

 lanceolate. 



Range. — Previously recorded from the west coast of Central 

 America south to Panama Bay. The range now is known to extend 

 as far south as northern Peru. 



