1904.] NATURAL SCIENCES OF PHILADELPHIA. 243 



caudal peduncle 1|. Opercle with radiating parallel striae. Gill-rakers 

 fine, slender, numerous, shorter than filaments. Color when fresh 

 in alcohol dull olivaceous-brown on upper surface, pale on sides, and 

 dilute or whitish on lower surface. Everywhere with more or less 

 dull brassy reflections. Longitudinal lines following courses of scales 

 pale. Opercle bright brassy. Fins dilute olive-yellow, unpaired 

 darker and slightly dusky marginally. Cheek silvery. Iris dull 

 golden, dusky above. Peritoneum black. Length 12^ inches. Del 

 Rio, Texas. 



Also three others with same data showing following: — Head 41- 

 to 41; depth 2f to 3^; D. iii, 22 to 25; scales to ba.se of caudal 35 to 

 36; total length 7| to 8f inches. 



These all appear to me to agree best with Cope's description. He 

 gives the orbit as 4 in head, but this is probably due to a different 

 method of measuring. If the figure of Idiohus tumidus^ is correct it 

 may represent a distinct form. The pectoral is said to almost reach 

 the ventral, and the radii are more numerous. Girard's figiu-e of 

 Carpiodes damalis^ shows a smooth opercle, large subopercle, and the 

 ventral inserted well posterior to the tip of pectoral. In my examples 

 of C. grayi the first developed dorsal ray extends back about f of the 

 entire length of the depressed fin. 

 Catostomus nigricans (Le Sueur). 



Color when fresh in alcohol dull olive, inclining to whitish below, 

 and everywhere with more or less silvery reflections. Back with five 

 rather indistinctly defined large saddle-like blotches composed of dusky 

 points. Lower surface of head silvery. Dusky dots on side of snout, 

 maxillary and upper opercle. Dorsal and caudal dull scarlet, margins 

 more or less dusky, especially that of former. Anal, pectoral and 

 ventral whitish. Hartford, Arkansas. 

 Minytrema melanops (Rafinesque). 



Del Rio, Texas. 



Moxostoma congestum (Baird and Girard). 



Head 4J; depth 4|-; D. ii, 11; A. ii, 7; P. i, 17; V. i, 9; scales 44 in 

 lateral line to base of caudal, and 2 or 3 more on latter; 7 scales, 

 obliquely from origin of dorsal to lateral line, and 5 between latter and 

 origin of ventral; 16 scales before dorsal; width of head If in its 

 length; depth of head If; snout 2yV; eye 5-|; width of mouth 3|; in- 

 terorbital space 2^; first developed dorsal ray 1^; base of dorsal l-f; 



* U. S. Mex. Bound. Surv., Ichth., 1859, p. 34, PI. 19, figs. 1-4. 

 2 Ex. Doc. No. 78, Rep. Expl. Surv. R. R. Miss. Pac, X. Fish., 1858, p. 218, 

 PI. 48, figs. 1-4. 



