Jordan and Evermann. Fishes of North America. 329 



548. MEDA FULGIDA, Girard. 



D. II, 7; A. 8; teeth 2, 5-5, 2. Body slender, elongate, compressed. 

 Head elongate, subconical, the snout rounded. Mouth large, subterminal, 

 slightly oblique, the lower jaw included ; maxillary extending to below 

 orbit. Second dorsal spine highest ; dorsal behind ventrals. Coloration 

 silvery. Closely allied to Plagopterus argentissimus, but with the eye a 

 little larger, the snout shorter, the lower jaw more prominent. Rio Gila. 

 (fnlyidus, shining.) 



MedafiilyUla, GIRARP, Proc. Ac. Nat. Sci. Phila., 1856, 191, Rio San Pedro, Arizona. (Type, 

 No. 154. Coll. Clark.) GUNTHER, Cat., vn, 263, 1868. JORDAN & GILBERT, Synopsis, 251, 

 1883. 



136. PLAGOPTERUS, Cope. 



Plagopterus, COPE, Proc. Amer. Phil. Soc. Phila., 1874, 301, (argentissimus). 



Body slender. Mouth terminal ; a barbel at the extremity of the maxil- 

 lary. Teeth 2, 5-4, 2, hooked, without grinding surface. Body entirely 

 scaleless. Fins as in Meda and Lepidomeda. Size small. (Tivlayj?, wound; 

 Trrepbv, fin ; in allusion to the armature of the dorsal fin.) 



549. PLAGOPTERUS ARGENTISSIMUS, Cope. 



Head 4 ; depth 6 ; eye 44-. D. II, 7 ; A. 10 ; teeth 2, 5-4, 2. Body slender. 

 Head rather broad, the muzzle slightly depressed, overhanging the rather 

 small, horizontal mouth. Lips thin, the maxilliary reaching front of eye. 

 Eye moderate. Dorsal fin entirely behind ventrals, the first spine curved, 

 longer than the second ; soft rays of dorsal thickened and ossified at base; 

 fifth ray of ventral bound to the abdomen by a membrane for nearly its 

 whole length ; pectoral rays osseous at base. Lateral line complete, slightly 

 deflexed. Color clear silvery ; back dusky, with minute black dots. 

 Length 21 inches. Colorado Basin in western Colorado, (Cope;) Fort 

 Yuma, (Gilbert.) (argentissimus, most silvery.) 



Plagopterus argenlissimus, COPE, Proc. Amer. Phil. Soc. Phila., 1874, 130, San Luis Valley, Col- 

 orado ; (Type, No. 15776. Coll. G. C. Newberry;) and Zool. Wheeler Surv., v, 640, pi. 

 xxvi, figs. 3, 3a, 1875, (1876); JORDAN & GILBERT, Synopsis, 252, 1883. 



Suborder HETEROGNATHI. 



Brain case not produced between the orbits. Lower pharyngeals rarely 

 modified into falciform structures bearing differentiated teeth. Jaws 

 with or without teeth; no pseudobranchiae. Adipose fin present or 

 absent. Fins with soft rays only. Fresh water fishes of the tropics, con- 

 stituting two families. They are really allied to the Cyprinidas and to the 

 other groups with modified anterior vertebrae, but in appearance they have 

 many analogies with the Salmonidcc,. (erepo^ , different ; yvdtioc, jaw.) 



ANALYSIS OF FAMILIES OF HETEROGNATHI. 



a. Supra-occipital confined to back of skull and with a very slight vertical crest. Adipose fin 

 wanting. ERYTHRINIP.*:, xxxvm. 



aa. Supra-occipital partly superior and carinated by a procurrent crest. Adipose fin well 

 developed. CHABACINID*, xxxix. 



