1874.] Idl [Coiic. 



MEDA, Giraid. 



Proceed. Acad. Nat. Sci., 1858, 192; U. S. aud Mexican Bound. Survey, 

 Iclithyoloo^y, p. 50. 



This genus resembles Plagopterus in the absence of scales, while it 

 differs in the absence of barbels and the reduction of the number of teeth 

 of the larger pharyngeal series to 4 — 4. Girard also asserts twice that 

 the dorsal spine is " articulated," a character not observed by me in any 

 species of the group. His figure of 31. fulgida represents tlie ventral 

 radii as articulated; but as there are other points in which it diffdrs 

 from the description, it is probably inaccurate. 



Meda fulgida, Girard. 



A small species from the Rio San Pedro, a tributary of the Gila, in 

 Southern Arizona. 



LEPIDOMEDA, gen. nov. 



Dorsal fin originating behind the line of the ventral s, which adhere to 

 the belly by the inner ray. Body scaled, lateral line present. Pharyngeal 

 teeth 4 — 4 in the inner row. No barbels, premaxillary series complete. 



This genus has the physiognomy of GUnostomus. The presence of 

 scales distinguishes it from Meda. The spinous rays are not articulated. 



Lepidomeda vittata, sp. nov. 



Form moderately stout, the greatest depth (at the first dorsal ray) 

 entering the length to the basis of the ciudal fin four and a quarter to a 

 third times. The head is wide and flat above, with decurved pterotics, 

 — and slightly depressed behind the interorbital region. Muzzle obtusely 

 descending, not prominent ; mouth terminal and descending to a point 

 below the anterior line of the pupil. Length of head, 3.75 times in total 

 length to basis of caudal fin. Orbit round, 3.75 times in length of head, 

 and 1.3 times in interorbital width. The latter is not uniform, but the 

 middle plane is elevated a little above the superciliary ridges, and 

 separated from them by a shallow groove. Nares sublateral. Teeth, 

 2.4 — 4.2. Preorbital tra]3ezoid. 



Scales small, covering the whole body, except a space behind the 

 pectoral fin, in twenty-six series above the lateral line, and fifty-six 

 transverse in front of the dorsal fin. Iladial formula, D. II. 7; C. 10- 

 A. I. 8 ; V. 1. VI.; P. 15. There are several peculiarities in the consti- 

 tution of the spines of the fins in which the species differs from Plagop- 

 terus argentissimus. Thus the second dorsal spine is wider than the first, 

 and so deeply grooved behind as to represent a V in section; it also 

 extends to the extremity of the first, while it is shorter in P. argentissimus^ 

 The remaining dorsal spines are less distinctly enlarged and ossified ; 

 those of the veutrals are less developed, and their apices, instead of being 

 free, continue into the terminal articulated portion. The pectaral radii 



