THE SHORE FISHES OF PERU 



317 



and on chest and abdomen, extending more or less on the fins; dorsal 

 spmes low, slightly graduated, but not increasing much in length after 

 the fourth or fifth, soft part anteriorly much higher, with concave 

 margin, longest rays 1,4 to 1.5 in head; caudal concave, the lobes 

 pointed, upper one the longer, anal spines short, graduated, the soft 

 part anteriorly rather high, with concave margin, the longest rays 

 1.25 to 1.3 m head; ventral inserted well behind base of pectoral, its 

 spine closely attached to first ray, contained 3.1 to 3.5 in head; pec- 

 toral broad, with obliquely rounded margin, not quite reaching tip 

 of ventral, 3.8 to 4.3 in length, 1.2 in head. 



Color in alcohol grayish brown; membranes of spinous dorsal 

 blackish. 



The foregoing description is based on three specimens 300, 310, and 

 370 mm. (233, 253, and 295 mm.) long. Two of these were secured by 





^r"tSii" -^JfiK*^ 





■-''••^'aiSsilS 



Figure 68. — Doydixodon laevifrons (Tschudi). From a specimen 270 mm. long, Mollendo 



Peru. (After Starks, 1906.) 



R. E. Coker, one at Lobos de Afuera and the other at Mollendo. The 

 third was taken by the Mission in a trammel net in San Juan Bay. In 

 addition to the large specimens listed, there are at hand eight juve- 

 niles 25 to 38 mm. (19 to 29 mm. to base of caudal) long, taken in 

 Independencia Bay, by W. L. Schmitt; also five specimens from 

 "Peru" collected by the Wilkes Exploring Expedition, which belong 

 to this genus and possibly this species. If so, considerable allowance 

 for changes with age must be made, for the outer teeth in the jaws 

 of these young are bicuspid and tricuspid, and the scales ctenoid, and 

 have only about 8 or 9 radii on the basal half, whereas those of the 

 large specimens have about 40. In the number of dorsal, anal, and 

 pectoral rays, in the number of scales, and in gill rakers they agree 

 with the large specimens. The proportions, when the great difference 

 in size is considered, also are in fair agreement. The following pro- 

 portions and enumerations are based on five juveniles, 19 to 47 mm. 



