THE SHORE FISHES OF PERU 337 



Mission were taken with trammel and gill nets, set near rocks, at 

 Cabo Blanco, Sechura Bay, Lobos de Afuera Bay, and Guanape 

 North Island. 



The numerous local names given for C. crusma presumably apply 

 to this species also, as the two apparently are not distinguished by 

 fishermen. The species are very similar in general appearance. 

 Upon close examination several differences, however, become evident. 

 These are stated in the comparison that follows. 



C. crusma 



Head large, 31.5 to 34 percent of length. 

 Pectoral fin long, generally reaching 



well beyond origin of anal, 30 to 37 



percent of length. 

 Dorsal with 13 (rarely 14) spines, and 



12 (occasionally 11 or 13) soft rays; 



posterior spines notably shorter than 



the fourth to about the eighth. 

 Anal with 12 (rarely 11 or 13) soft 



rays, its margin broadly rounded. 

 Caudal moderately forked, the upper 



lobe equal to or little longer than 



head. 



C. intercrusma 



Head smaller, 27 to 31 percent of length. 



Pectoral fin shorter, usually not quite 

 reaching origin of anal, 28 to 30 per- 

 cent of length. 



Dorsal with 12 spines and 14 (occasion- 

 ally 13 or 15) soft rays; the spines 

 following the third, all of about equal 

 length. 



Anal with 13 or 14 soft rays, its margin 

 forming an acute angle. 



Caudal deeply forked, the upper lobe 

 longer than head by fully an eye's 

 diameter in large examples. 



Range. — Peru, probably south to Juan Ferndndez Island, Chile. 

 Genus POMACENTRUS Lacepede, 1802 



Body ovate, strongly compressed; head short; mouth small, terminal; 

 teeth fixed, in a single series in each jaw, compressed, with straight or 

 slightly truncate cutting edges; suborbital with lower margin free, 

 serrate; margin of peropercle serrate; scales large, ctenoid, missing 

 only about the mouth; dorsal fin continuous, with about 12 or 13 

 graduated spines; anal with 2 spines and about 12 to 14 soft rays. 



These fishes generally live about rocks and on coral reefs. A single 

 species comes within the scope of the present work. 



POMACENTRUS RECTIFRAENUM Gill 



Pomacentrus redifraenum Gill, 1862, p. 148, Cape San Lucas, Baja California 

 (original description). — Regan, 1913, p. 279, Lobos de Tierra, Peru. — Meek 

 and HiLDEBRAND, 1925, p. 698, Panama Bay (synonymy; description; range). 



Head 3.0 to 3.2; depth 2.0 to 2.2; D. XII (rarely XI), 15 or 16; 

 A. II, 12 or 13; P. 21 or 22; scales (vertical series along middle of side) 

 26 to 28; vertebrae 25 (one specimen dissected). 



Body ovate, strongly compressed, its greatest thickness about 2.5 

 in its depth; back elevated; dorsal outline anteriorly more strongly 

 convex than the ventral; caudal peduncle moderately short, 2.0 

 to 2.2 in head; snout moderately blunt, 3.4 to 4.1; eye 2.8 to 3.3; 

 interorbital 3.8 to 4.4; mouth small, slightly oblique, terminal; 



