THE SHORE FISHES OF PERU 331 



the eye apparently is larger, the snout and maxillary are a little longer, 

 the upper jaw projects more strongly, the lips are notably broader, the 

 ventral and pectoral fins are less fleshy, the color is decidedly darker, 

 and pale blotches and bars anterior to beginning of soft part of dorsal 

 are missing. As only one specimen of C. variegatus, of the many at 

 hand, is large enough to come within the range of length of the speci- 

 men of C. elongaius, the proportions based on it alone are directly 

 comparable. In the following list the proportions are all given in the 

 percent of the length to base of caudal, those based on the single 

 specimen of C. variegatus, which is 280 mm. long to base of caudal, 

 being given first in each instance, and the range of those based on the 

 4 specimens of C. elongatus second. Depth 40, 31.5 to 33.5; eye 5.7, 

 6.0 to 6.7; snout 11.7, 11.6 to 12.0; maxillary 9.2, 9.2 to 10.3. Differ- 

 ences in the same proportions still are evident if specimens of C. 

 variegatus ranging upward of 250 mm. in total length are compared 

 with the type material of C. elongaius, for in seven specimens of C. 

 variegatus, the following range was found: Depth 36.5 to 40; eye 5.7 to 

 6.25; snout 9.4 to 11.7; maxillary 7.2 to 9.2. 



Range. — Kno%\Ti only from the type material from Lobos de Tierra 

 Bay, and Lobos de Afuera Bay. 



Family POMACENTRIDAE 



Body usually short and deep, well compressed; mouth small, usually 

 terminal; teeth conic or incisorlike, in one or more series or in a narrow 

 band in each jaw, none on vomer or palatines; preorbital sheathing 

 maxillary; nostril single; giUs 3^, slit behind the last small or obsolete; 

 lateral line ending under soft part of dorsal; scales large, ctenoid; 

 dorsal fin long, continuous, with rather numerous spines (12 to 14 in 

 Peruvian genera) ; anal with 2 spines, its soft part similar to that of 

 dorsal; ventral thoracic, with 1 spine and 5 soft rays. 



This is a family of small, usually brilliantly colored fishes, which live 

 mostly on coral reefs and among rocks where they feed principally on 

 small animals and plants. 



KEY TO THE GENERA 



a. Teeth conical, each jaw with an outer, somewhat enlarged, series, followed 

 anteriorly by 2 or more series or by a narrow band of small teeth; suborbital 



adnate to cheek Chromis (p. 332) 



aa. Teeth more or less compressed, in a single series in each jaw; suborbital 

 adnate or free from cheek. 

 h. Margin of preopercle serrate; lower margin of suborbital free, serrate; teeth 

 with straight or slightly truncate cutting edges,. Pomacentrus (p. 337) 

 hh. Margin of preopercle entire; lower margin of suborbital, if free, not serrate. 

 c. Teeth broad, more or less bicuspid; lower margin of suborbital free for 

 its entire length; dorsal with about 12 to 14 soft rays. 



Abudefduf (p. 338) 

 cc. Teeth narrow, with straight or slightly rounded cutting edges; lower 

 margin of suborbital adnate to cheek anteriorly, somewhat free pos- 

 teriorly; dorsal with about 17 to 19 soft rays Nexilosus (p. 340) 



