426 BULLETIN 189, UNITED STATES NATIONAL MUSEUM 



This species is close to M. cephalus, from which it differs in having 

 rough scales, which cover most of the caudal fin and seem to be devel- 

 oped earlier in life on the gill covers. In young M. cephalus, as well 

 as in M. curema, the opercles are bright silvery in the young, whereas 

 they are brownish and translucent in M. peruanus, the gills generally 

 being visible tlii'ough the covers. Small specimens of M. cephalus 

 and M. curema are bright silvery, whereas those of M. peruanus are 

 without a silvery sheen. In dentition it differs from the two species 

 mentioned, as shown by the descriptions. 



Two lots of small specimens collected by R. E. Coker at Callao 

 and Pacasmayo, Peru, are also of this species. They are part of the 

 specimens reported as M. cephalus by Evermann and Radcliffe (1917, 

 p. 49). 



A large lot of small specimens collected by W. L. Schmitt, in fresh 

 water in the Rio Moche, near Salaverry, Peru, is somewhat bother- 

 some. They all come within the range of length of the specimens 

 secured by the Mission. They have some characters in common with 

 the specimens herein described as peruanus, that is, the scales are 

 provided with prominent concentric rings and are rough to the touch, 

 and they extend on the fins somewhat. The teeth in most of them 

 are arranged as stated in the foregoing description, though a few have 

 rather numerous teeth between the two main rows in the upper jaw, 

 and some minute ones behind the labial series in the lower jaw. 

 Furthermore, they are silvery in color, have no dark spots on the 

 head, and have comparatively few bro^vn points on the body. These 

 specimens tend to form a "connecting link" between those herein 

 described as peruanus and those recognized as rammelshergii. It is 

 obvious that more specimens and a much more extended study of 

 specimens from a wider range of localities are necessary before the 

 exact relationship of the different species, subspecies, and varieties of 

 Mugil can be determined. 



Range. —Coast of Peru. To date taken only between latitude 5°52' 

 and 14°13' S. 



MUGIL CUREMA Cuvier and Valenciennes 



Liza 



Mugil curema Cuvier and Valenciennes, 1836, p. 87, Brazil and Martinique 

 (original description). — Meek and Hildebrand, 1923, p. 279, both coasts of 

 Panama (synonymy; description; range). 



Mugil ciliilabis Cuvier and Valenciennes, 1836, p. 151, "Callao de Lima," Peru 

 (original description. It is not evident from the description wherein this 

 supposedly new species differs from M. curema. The anal formula. III, 9, 

 is correct for curema, and there is nothing in the description of the teeth 

 inconsistent with those of that species. Just why ciliilabis was referred to 

 the genus Myxus, and later to Neomyxus, by authors is not clear) . 



Head 3.8, 3.9; depth 3.9, 4.3; D. IV-I, 8; A. II, 9; P. 15. 

 Body fairly elongate, compressed; ventral outline a little more 

 strongly convex than the dorsal; caudal peduncle rather strongly 



