352 



MEMOIRS OF THE CARNEGIE MUSEUM. 



Alimentary canal straight, without convolutions or bends, the thin-walled 

 stomach lying lengthwise and giving rise to a short, thin intestine, which merges 

 into the much longer and larger, but thin-walled, large intestine which appears to 

 be filled with minute grains of sand. 



2. Homodiaetus maculatus (Steindachner). 

 Stegophilus maculatus Steindachner, Denk. Ak. Wiss., Wien, XLI, 1879, p. 25, 

 IV, fig. 2 (La Plata); Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), 



II, 1889, p. 54; Occasional Papers Cal. Acad. Sci., I, 1890, p. 343; Proc. U. S. 

 Nat. Mus., XIV, 1891, p. 37. 



Henonemus maculatus Eigenmann, Reports Princeton Univ. Exped. Patagonia, 



III, 1910, p. 401. 



Habitat. — La Plata, in Province Buenos Aires; Uruguay Basin. 



Known from the type, a specimen 105 mm. long, and 

 7545a-d, C. M., 67-69 mm. Uruguayana, Feb. 6, 1907. J. D. Haseman. 

 7546rt-c, C. M., 64-70 mm. Cacequy. Feb. 2, 1907. J. D. Haseman. 



Head 5.75-6.75; depth 6-9; D. 9; A. 7; P. 6; eye 3.66-4 in head, equal to snout 

 or interorbital; maxillary barbel filamentous, equal to the eye, the inner barbel 

 much smaller; seven series of teeth in the upper jaw and lip, five in the lower; about 

 seven, graduate, opercular spines, about nine larger interopercular spines; gill- 

 membrane forming a free fold across the isthmus; anal behind the dorsal. In the 

 type, a series of spots along the back, another row of spots along the middle of the 

 sides; two or three rows of smaller spots between the two; base of caudal with a 

 dark cross-bar, several small spots along the upper edge of the caudal; tips of the 

 caudal dark spotted. 



Fig. 26. Homodiastus maculatus (Steindachner). After Steindachner. 



