EIGENMANN: the freshwater fishes of BRITISH GUIANA 239 



48; Occasional Papers Cal. Acad. Sci., I, 1890, 446 (Cudajas; Obidos); Proc. 

 U. S. Nat. Mus., XIV, 1891, 43.— Eigenmann, Repts. Princeton Univ.. Exp. 

 Patagonia, III, 1910, 411. 



Choetostomus cirrhosus GtJNTHER, Catalogue, V, 1864, 247 (Essequibo, British 

 Guiana). — Hensel, Archiv flir Naturg., I, 1870, 76 (stony mountain streams). 

 — Vaillant, Bull. Soc. Philom., (7), IV, 1880, 155 (Calderon).— Stein- 

 DACHNER, "Flussfische Siidamerika's," iv, 1882, 7 (Rio Huallaga). — Perugia, 

 Ann. Mus. Genova, (2), XVIII, 1897, 21 (Rio Beni). 



Xenocara cirrhosa Regan, Trans. Zool. Soc. London, XVII, 1904, 256 (Rio Para- 

 guay; Amazon; Guiana; Trinidad). 



Choetostomus variolus Cope, Proc. Acad. Nat. Sci. Phila., 1871, 288 (Ambyiacu). — 

 Eigenmann and Eigenmann, Proc. Cal. Acad. Sci., (2), II, 1889, 64; Occa- 

 sional Papers Cal. Acad. Sci., I, 1890, 442. 

 Three specimens, 48 to about 100 mm. Ireng River near Holmia. (C. jNI. 



Cat. No. 1523; I. U. Cat. No. 11949.) 



Head 2.85-3; depth at tip of occipital 2.4 in the head; width of head an orbital 



diameter less than its length; interorbital 2.4 in the head; mandibular ramus 2-3 



in the interorbital; D. 1,7; A. 1,4; eye 5.5 in the head in the largest specimen; 



about twelve interopercular spines, the longest 4.5 in the head. 



Tentacles numerous, the naked area reaching half-way to the posterior margin 



of the eye in the largest specimen, which is a male; six plates between the dorsals, 



ten between the anal and caudal, and twenty-four along the sides. 



Last dorsal ray scarcel.y reaching the spine of the adipose; base of dorsal a 



little greater than its distance from the adipose; dorsal spine equal to snout and 



eye; ventrals about reaching middle of anal; pectoral spine reaching third fifth 



of ventrals. 



Black, with faint white spots; dorsal and caudal with dark spots along the 



rays; pectorals and ventrals spotted or plain. 



106. Ancistrus hoplogenys (Giinther). 

 Choetostomus hoplogenys Gunther, Catalogue, V, 1864, 247 (River Capin, Para). 

 Ancistrus hoplogenys Eigenmann and Eigenmann, Proc. Cal. Acad. Sci., (2), II, 



1889, 48; Occasional Papers Cal. Acad. Sci., I, 1890, 448 (Tajapuru); Proc. 



U. S. Nat. Mus., XIV, 1891, 43.— Eigenmann, Repts. Princeton Univ. Exp. 



Patagonia, III, 1910, 411. 

 Xenocara hoplogenys Regan, Trans. Zool. Soc- London, XVII, 1904, 255 (Guiana; 



Amazon; Rio Paraguay). 



