THE SHORE FISHES OF PERU 431 



now at hand. However, the difference is sHght. The average number 

 of spines in the first dorsal, and the average number of anal rays is a 

 little greater in the Chilean specimens. These differences are shown 

 in table 3. It is probable also thiit the specimens from Chile have a 

 greater average number of vertebrae, as two of three specimens dis- 

 sected had 51 vertebrae, and the other one had 52, whereas among 

 seven specimens from Peru four had 49, two had 50, and one had 51 

 vertebrae. 



The "pejerrey" has been reported by the Mission (1943, p. 273) as 

 numerous in the vicinity of Pisco and Callao, Peru, and as an important 

 and highly prized food fish. 



Range. — Coast of Peru, from about Lobos de Tierra Island (lat. 

 6°27' S.) southward; represented in Chile by a subspecies or variety. 



Genus EURYSTOLE Jordan, 1895 



Body sharply compressed; head short, deep, compressed, with 

 margin of gill covers little convex ; preopercular angle with a very small 

 flat adherent point, or "spine"; interorbital convex; eye large, round; 

 premaxillaries protractile; gape strongly curved; teeth in the jaws well 

 developed; scales cycloid, adherent, small to moderately large; first 

 dorsal with about 3 to 5 flexible spines, not nearly reaching second 

 dorsal if deflexed, its origin at or near vertical from origin of anal; 

 caudal forked; anal long, with about 25 to 30 rays; side with a broad 

 silvery band. 



Myers and Wade (1942, p. 126) erected a new genus, Nectarges, in 

 which they placed three new species described in the same paper, 

 including the one discussed in the present catalog. The new genus 

 was defined as differing from Eurystole chiefly in having smaller 

 scales ; in having more scales on the base of the anal, forming a sheath ; 

 and in having the silvery lateral band less constricted on the caudal 

 peduncle. These differences I regard as not of generic value, though 

 Nectarges may be retained as of subgeneric rank. 



EUEYSTOLE NOCTURNUS (Myers and Wade) 



Eurystole eriarcha Nichols and Murphy (probably not of Jordan and Gilbert), 

 1922, p. 506, North Chinca Island, Peru (18 specimens reported). 



Nectarges nodurnus Myers and Wade, 1942, p. 133, Guayaquil, Ecuador; and 

 Paita, and North Chincha Island, Peru (original description). 



Head 4.4 to 5.0; depth 4.4 to 5.4; D. Ill or IV-I, 10; A. I, 25 to 28; 

 P. 12 or 13; scales 53 to 57, 8 complete through series between bases 

 of second dorsal and anal; vertebrae 40 (one specimen dissected). 



Body strongly compressed, especially ventrally; dorsal outline only 

 gently convex; ventral outline strongly convex anteriorly; caudal 

 preduncle strongly compressed, its depth 2.2 to 2.8 in head; head 

 short, deep, its greatest depth approximately equal to its length with- 

 out snout; margin of opercle slightly concave just below its upper 



