THE SHORE FISHES OF PERU 43 



one the larger, reaching about a thnd the distance to midUne of jaw; 

 teeth with a rather long narrow nonserrated cusp with an almost 

 straight anterior margin, posteriorly with a small notch followed by a 

 small cusp and sometimes by serrae on an expanded base, the middle 

 ones especially those of lower jaw reduced; dermal denticles narrow, 

 sharply pointed distally, usually with a large median keel and a small 

 one paralleling it on each side, all extending beyond the margin, caus- 

 ing deep indentations; first dorsal originating about over beginning of 

 distal third of pectoral, its greatest height about equal to interorbital 

 space, its distal margin concave; predorsal length 2.2 to 2.4 in length 

 anterior to upper lobe of caudal; distance between dorsal fins 3.2 to 

 3.8; second dorsal small, its origin a little in advance of that of anal; 

 upper lobe of caudal moderately long, 3.0 to 3.2 in length anterior to 

 its base; lower lobe exserted anteriorly, nearly as high as first dorsal; 

 anal nearly of same size and shape as second dorsal, its base 4.5 to 

 5.8 in head; ventral short, inserted about equidistant from inner distal 

 angle of pectoral and origin of anal, its distal margin nearly straight; 

 pectoral moderate, somewhat rounded distally, inserted under fourth 

 gill slit, its greatest length 5.6 to 6.2 in length anterior to base of upper 

 lobe of caudal. 



Color of preserved specimens bluish gray above; pale underneath. 

 The first dorsal in embryos conspicuously white at base anteriorly 

 and distally posteriorly, the distal margin of dark part of fin with 

 black margin; the posterior part of second dorsal distally also con- 

 spicuously white, lower lobe of caudal at its deepest concavity, and 

 the tip of upper lobe conspicuously black; pectoral fin with pale mar- 

 gin. These markings, though persisting, are less conspicuous in 

 small adults, 363 and 384 mm. long. 



The foregoing account is based on nine embryos, 225 to 240 mm. 

 long, and two young adults, 363 and 384 mm. long. Ir addition to 

 these young there are at hand a head of an individual 152 cm. long 

 and the jaws and part of the fins of another large adult (length un- 

 known). The teeth in these large specimens are much more conspicu- 

 ously serrate on the base posteriorly than in the young, the first serra 

 often being only a little larger than the succeeding one; anterior parf 

 of expanded base also often with two to several serrae. The pectoral 

 fins are more pointed, and there remains a mere suggestion of a pale 

 margin, the other pale markings of the young having entnely dis- 

 appeared. The first dorsal and the pectoral (the only fins preserved) 

 are distally profusely dotted and spotted with black. The following 

 proportions are based on measurements made by Mr. Lobell of four 

 fresh individuals, all females with embryos, 152 to 158 cm. long: 

 Head 4.0 to 4.25 in length anterior to base of uppper lobe of caudal; 

 predorsal length 2.15 to 2.35; distance between dorsal fins 3.1 to 3.3; 

 upper lobe of caudal 3.5 to 3.9; pectoral 4.8 to 5.0. Snout 2.3 to 2.7 

 in head to first gill slit; eye 8.3 to 9.7; base of anal 4.5 to 5.2. These 



