300 BULLETIN 189, UNITED STATES NATIONAL MUSEUM 

 Genus BAIRDIELLA Gill, 1861 



Body moderately elongate, compressed; head fairly short, conical; 

 mouth moderate, oblique to nearly horizontal; teeth small, no canines, 

 generally in one or a few rows; margin of preopercle strongly serrate; 

 skull little cavernous; gill rakers slender; second anal spine moderate 

 or large. 



A single species, new to the fauna of Peru, is represented in the 

 collections now at hand. 



BAIRDIELLA ENSIFERA (Jordan and Gilbert) 



Sciaena ensifera Jordan and Gilbert, 1882c, p. 313, Panama Bay; also "Punta 

 Arenas," presumably Costa Rica (original description; compared with 

 B. armata and B. icistia). 



Bairdiella ensifera Meek and Hildebrand, 1925, p. 632, Panama Bay (synonymy; 

 description; range, its northern limit probably incorrectly stated). 



Head 3.4, 3.5; depth 3.1, 3.3; D. X-I, 23, X-I, 23; A. II, 8; II, 8; 

 P. 17, 17; scales 67, 71. 



Body moderately elongate, compressed, its greatest thickness equal 

 to about half its depth; back elevated; profile nearly straight over 

 eyes, strongly convex at nape; head fairly short, compressed; caudal 

 peduncle long, rather slender, 2.8, 2.9 in head; snout conical, 4.6, 4.9; 

 eye vertically slightly elongate, 3.6, 3.9; interorbital 4.5, 4.6; mouth 

 rather large, oblique, terminal; maxUlary reaching a little beyond 

 middle of eye, 2.2, 2.25 in head; teeth in the jaws minute, anteriorly 

 in a band, laterally in a single series; margin of preopercle serrate, the 

 lowermost spine directed downward; gill rakers slender, those at angle 

 about half length of eye, 22, 22 on lower and 9, 10 on upper limb of 

 first arch; lateral line somewhat arched anteriorly, reaching middle 

 of body about under middle of second dorsal; scales strongly ctenoid, 

 reduced anteriorly, the rows above lateral line not parallel with it, 9, 

 10 between lateral line and base of first dorsal spine, and 6, 6 between 

 it and middle of base of second dorsal; dorsal fins close together (the 

 spine herein counted with the second fin not closely attached to it), 

 the spmes moderately strong, the fourth spine longest, notably longer 

 than longest soft rays, 1.6, 1.6 in head, margin of second dorsal convex; 

 caudal very slightly double concave; anal small, the second spine 

 greatly enlarged; reaching nearly to base of caudal if deflexed, 1.3, 1.3 

 in head, margin of fin concave, its origin under middle of second dorsal, 

 its base 2.2, 2.4 in head; ventral large, inserted a little behind base of 

 pectoral, 1.2, 1.2 in head; pectoral moderate, failing to reach tip of 

 ventral, 1.15, 1.2 in head, 4.0, 4.2 in length. 



Color sUvery gray above; bright silvery below; rows of scales on 

 upperparts of body with indistinct dark lines; membranes of spinous 

 dorsal quite dusky; second dorsal and caudal dusky toward their 

 margins; other fins mostly pale yellowish; axU of pectoral dark. 



