85. PERCIDJE — HADROPTERUS. 505 



brication takes place after the fashion of the Scia^noids ; instead of 

 longitudinal series, they constitute transverse oblique series. As to the 

 coloration, it is but imperfectly preserved. Transverse bands of deep 

 chestnut alternate with white or yellowish ones. These bands or fas- 

 ciJB are better defined below the lateral line than above it, where they 

 are sometimes interrupted. The head is brown, with a vertical black 

 streak across the orbits. The fins are yellowish, unicolor, except the 

 first dorsal, which is margined with black. During life we imagine this 

 fish to be one of the prettiest inhabitants of the fresh waters of this 

 continent." {Girard.) Chihuahua River, Mexico. The types of this spe- 

 cies are lost, but it is doubtless closely allied to A. evides, 



(Diplesion fasciatus Girard, Proc. Acad, Nat. Sci. Phila. 18o9, 101.) 

 262.— IIADKOPTERUS Agassiz. 

 {ffypohomus Cope: Plesioperca Vaillant.) 

 (Agassiz, Amer. Jouru. Sci. Arts, 1854, 305: type Hadropterus nigrofasciatus Ag.) 



This genus differs from Alvordius only in the absence of the caducous 

 ventral plates, the belly being covered with persistent scales, similar to 

 those on the sides, {ddpoe;^ strong ; -nr^pih^ fin.) 



a. Anal fin large, not smaller than the second dorsal. 



h. Scales small, moro than 75 in the lateral line; body elongate, little compressed ; 

 D. XV-15. {Hypohomua* Cope.) 



■ySO. BI. aui'a.ntia.cus (Cope) Jor. 



Form elongate ; caudal peduncle slightly contracted ; orbit smaller 

 than length of muzzle, 4 in head, excluding the opercular spine; man- 

 dibles shorter than muzz'e ; cheeks and operculum covered with small 

 scales; scales very small, covering the ventral line; gular region 

 smooth ; third dorsal ray longest, fin outline rapidly descending poste- 

 riorly; first anal ray below first of second dorsal ; caudal fin even. 

 Golden-brown above, with a series of small round brown spots nearer to 

 the basis of the dorsal tin than the lateral line ; the latter traversed by a 

 broad black band, which passes on sides of head around muzzle; below 

 bright citron yellow ; fins unspotted. Head 4;^; dei)th G. 1). XV-15; 

 A. 11, 11; Lat. 1. about 85. L. 4J inches. (Cope.) Headwaters of Ten- 

 nessee Kiver. 



{Cottogaater auranliacus Cope, Jonrn. Acad. Nat. Sci. Phila. 1869, 211 : Unpohomua 

 aurantiacus Cope, I'roc. Amer. Philos. Soc. 1870, 451: Hadropterus auranliacus Jor- 

 dan, Man. Vert. 221.) 



hi). Scales large, less than (10 in the lateral line; body rohnst, more or less compressed; 

 dorsal XII-12. (Hadropteriiat ) 



* Hypohomus Cope, Proc. Amer. Philos. Soc. 1870, 451: type Cottogaster aurautlacua 

 Cope. (u;roj, below ; 6/«o5, uniform.) 

 i Plesioperca, Vaillant. 



