158 BULLETIN 189, UNITED STATES NATIONAL MUSEUM 



projecting strongly, but scarcely entering dorsal profile; maxillary 

 largely concealed under preorbital, reaching a little beyond middle of 

 eye, 2.1 to 2.25 in head; teeth rather large, distally more or less pointed 

 like an arrowhead, present in 2 more or less irregular series in the jaws 

 and on vomer; gill rakers moderately slender, those at angle about 

 two thirds length of eye, 14 to 17 on lower and 3 to 5 on upper limb of 

 first arch; lateral line complete, high anteriorly; scales small, cycloid, 

 partly or all lost in specimens at hand; first dorsal separated from the 

 second by a distance equal to about half diameter of eye, its origin 

 slightly behind base of uppermost ray of pectoral, notably higher than 

 second dorsal, its longest ray 2.2 to 2.6 in head; second dorsal deeply 

 indented at beginning of about its posterior third, its origin a little in 

 advance of that of anal; caudal fin damaged in the smaller specimens 

 studied, certainly emarginate in a specimen 165 mm. long and deeply 

 concave in the large ones (270 and 420 mm. long) ; anal similar to 

 second dorsal, with similar indentation; ventral inserted a little 

 behind margin of preopercle, scarcely reaching midlength of pectoral 

 2.2 to 2.35 in head, 6.7 to 7.3 in length; pectoral long, reaching opposite 

 base of the fifth to seventh ray of anal, 1.3 to 1.55 in head, 4.15 to 4.6 

 in length. 



The color of the largest specimen at hand was described by Ever- 

 mann and Radcliffe (see reference above) as, "dusky on back, becom- 

 ing lighter on belly; fins dusky; some of lower rays of pectoral, black." 

 A smaller specimen, according to the same authors, was "rosy, dusky 

 on back, silvery on belly; opercle blackish; fins blackish; anterior anal 

 rays and shortened rays in center of second dorsal and anal, whitish." 

 These specimens are now greatly faded. 



The Mission furnished two specimens, 165 and 270 mm. (140 and 230 

 mm. to base of caudal) long. The smaller one was taken in a purse 

 seine at night, 3 mUes off Canete, and the larger one was removed from 

 the stomach of a yellowfin tuna, Thunnus macropterus, caught by 

 trolling, at latitude 9° 9' 75" S., longitude 75° 32' W., or about 55 

 mUes west of Chimbote Bay. Nine other specimens, 155 to 420 mm. 

 (135 to 365 mm. to base of caudal) long, collected by R. E. Coker at 

 Paita and Callao, were studied. The last-mentioned specimens are 

 the ones reported by Evermann and Radcliffe (see reference above). 

 The specimen from near Caiiete is abnormal in that the second dorsal 

 is fully divided, the anterior part having 16 rays and the posterior 21. 



This species is close to M. productus ( Ayers) of the Pacific coast of the 

 United States and of Baja California. According to 9 specimens of 

 M. productus studied, it differs slightly in the rather more numerous 

 rays in the second dorsal and also in the anal. In the 9 specimens 

 examined 1 has 37 rays in the second dorsal, 2 have 38, 2 have 39, 

 2 have 40, and 2 have respectively 40 and 41, whereas among 11 

 specimens of M. gayi, 1 has 35 rays in the second dorsal, 2 have 36, 3 

 have 37, 2 have 38, and 3 have 39. In 9 specimens of M. productus 



