220 BULLETIN 189, UNITED STATES NATIONAL MUSEUM 



Steindacliner (see references above) unfortunately omitted the enu- 

 meration of gill rakers, both in S. mazatlana and S. peruana, perhaps 

 the most important single diagnostic character of the species of the 

 genus. As gill-raker counts are not given, it is uncertain whether the 

 two nominal species are actually identical. 



Range. — Mazatldn, Mexico, to the Galdpagos Islands, and Peru if 

 S. peruana is identical with S. mazatlana. 



Genus NEPTOMENUS Giinther, 1860 



Body oblong, compressed; head compressed, rather obtuse; mouth 

 wide, nearly terminal; premaxillaries not protractile; teeth in a single 

 series in each jaw, none on vomer, palatines, or tongue; lateral line 

 without definite bony scutes (at least in the American species) ; 

 first dorsal composed of seven or eight short spines connected by 

 membranes; second dorsal and anal similar in shape, somewhat 

 elevated anteriorly, the anal much shorter; no finlets; ventral attached 

 to abdomen by membrane; pectoral much longer, pointed. 



A species apparently belonging to the genus Neptomenus, which 

 has a representative in New Zealand, occurs in Peru. 



NEPTOMENUS CRASSUS Starks 



cojinoba 

 Figure 49 



Neptomenus crassus Starks, 1906, p. 784, fig. 8, Callao, Peru (original descrip- 

 tion). — Evermann and Radcliffe, 1917, p. 57, Callao and Mollendo, Peru 

 (description). — Nichols and Murphy, 1922, p. 507, Central Chincha Island, 

 and Pescadores Islands, off Ancon, Peru (notes on the great abundance, 

 schooling, and methods of catching). 



Seriolella crassus Fowler, 1940b, p. 768, fig. 47, Callao, Peru (identified from a 

 painting and a sketch; very probably not Seriolella, which is described as 

 having vomerine teeth and a denticulate preopercle). 



Head 2.75, 2.8; depth 2.85, 2.95; D. VII-I, 27, VITI-I, 26; A. Ill, 

 19,111, 17;P. 22, 21. 



Body rather deep, compressed; dorsal and ventral profiles anteriorly 

 about evenly convex; caudal peduncle compressed, its depth 5.1, 5.35 

 in head; head large, deep; snout fairly blunt, 4.1, 3.9 in head; eye large, 

 4.1, 3.9; interorbital 3.9, 3.65; mouth oblique; lower jaw projecting 

 slightly; maxillary rather narrow, with a supplemental bone, reaching 

 anterior margin of pupil, 3.2, 3.1 in head; teeth in each jaw small, 

 even, in a single close-set series, none on vomer, palatines, or tongue; 

 gill rakers compressed, about as long as pupil, 17, 16 on lower limb, 

 and 6, 6 on upper limb, of first arch; lateral line apparently nearly 

 straight (its course difficult to see because scales are mostly lost in 

 specimens at hand), without scutes; spines of first dorsal short and 



