THE SHORE FISHES OF PERU 243 



supplemental bone; teeth pointed or conical, no canines, wanting on 

 vomer, palatines, and tongue; preopercle usually serrate; opercle 

 without spines; branchiostegals 6 or 7; gills 4, a slit behind the fourth; 

 gill membranes separate and free from the isthmus; lateral line com- 

 plete, usually not extending on caudal fin; scales moderate or rather 

 large, firm, ctenoid; dorsal fin single, more or less deeply notched, 

 with 10 to 14 strong spines, depressible in a groove; caudal more or 

 less concave; anal with 3 spines, the soft part of fin similar to that 

 of dorsal, though generally shorter; ventral fins thoracic, each with 

 a rather slender spine and 5 soft rays. 



KEY TO THE GENERA 



o. Margin of preopercle rather strongly serrate, 1 or more serrae at angle much 

 enlarged, those on its horizontal limb directed forward; body rather elongate, 



little compressed, the depth about 3.33 in length Conodon (p. 243) 



aa. Margin of preopercle finely serrate, the serrae at angle if present not much 



enlarged, those on its horizontal limb if present not directed forward; body 



usually deeper and more compressed. 



b. Anal fin short, with 6 to 8 soft rays; scales moderately small, about 65 to 80 



oblique series on side above lateral line. 



c. Body fairly elongate; back not greatly elevated; depth about 2.8 to 3.4 in 



length; gill rakers well developed, 20 to 25 on lower limb of first 



arch Isacia (p. 246) 



cc. Body deeper; back rather strongly elevated; depth about 2.0 to 2.5 in 

 length; gill rakers small, about 12 to 14 on lower limb of first arch. 

 d. Anal spines small, more or less graduated, the second scarcely if at all 

 stronger than the third; lips thin; no scales on dorsal or anal. 



Orthopristis (p. 248) 



dd. Anal spines much stronger, the second usually notably longer and 



stronger than the third; lips thick; small scales on interradial 



membranes of soft parts of dorsal and anaL_ Anisctremus (p. 249) 



bb. Anal fin longer, with 9 to 13 soft rays; scales larger, about 45 to 55 oblique 



series on side above lateral line. 



e. Small scales present on interradial membranes of soft parts of dorsal and 



anal; ventral fins inserted behind base of pectorals. 



Brachydeuterus, (p. 252) 



ee. Scales wanting on interradial membranes of soft parts of dorsal and anal; 



ventral fins inserted under base of pectorals- Pomadasys (p. 256) 



Genus CONODON Cuvier and Valenciennes, 1830 



Body rather elongate, somewhat robust; back not greatly elevated; 

 mouth moderate, oblique; maxillary generally reaching below anterior 

 part of eye; teeth in each jaw in a band, the outer ones in each jaw 

 more or less enlarged, conical; preopercular margin rather strongly 

 serrate, with one or more serrae at angle enlarged, those on horizontal 

 limb directed forward; soft dorsal and anal each with a low sheath of 

 scales at base, and with small scales on interradial membranes; 

 second anal spine generally enlarged; anal with tliree rather strong 

 spines and seven or eight soft rays. 



A single species, which apparently is new, comes within the scope 

 of the present work. 



