226 MEMOIRS OF THE CARNEGIE MUSEUM 



Plecostomus verrcs Regan, Trans. Zool. Soc. London, XVII, 1904, 209. 

 Hypostomus commersonii (not of Cuvier and Valenciennes) Muller and Troschel, 



in Schomburgk, Reisen, III, 1848, 631 (Takutu). 

 ? Hypostomus pantherinus Kner, Denkschr. Akad. Wiss. Wien, VII, 1854, 267 



(Rio Guapore). 

 Plecostomus bicirrhosus Gunther, Catalogue, V, 1864, 231, part. 



One specimen, 273 mm. Mahaica. (I. U. Cat. No. 11961.) 



Two specimens, 128-435 mm. Georgetown. (C. M. Cat. No. 1540.) 



There are also five specimens in the Amsterdam Museum, probably from 

 Surinam. 



Head 3.25-3.5; depth 4.66-6; D. 1,7; A. 1,4; scutes 28. Eye 6-8 in the head; 

 interorbital 2.25 in the head; mandibular ramus about 3 in the interorbital. 



Occipital with a well-marked median ridge, bordered behind by a median and 

 several lateral plates; supraocular ridge continued on the upper part of the sides 

 as a keel; all plates, except those on the caudal peduncle, keeled. 



Dorsal spine about equal to head or pectoral spine; base of dorsal equal to 

 its distance from the tip of the spine of the adipose. 



Olive, everywhere with darker spots, smallest on the head and largest on the 

 belly; fins banded in the young, spotted in the old. 



In the specimen at the Berlin Museum mentioned by Schomburgk as commer- 

 sonii the occipital is bordered by a large median and one small lateral plate on each 

 side. 



93. Plecostomus emarginatus Cuvier and Valenciennes. 



' ' Warra-warra " ; " Morutta " ; " Wacari . ' ' 



Hypostomus emarginatus Cuvier and Valenciennes, Hist. Nat. Poiss., XV, 1840, 



500 (Brazil).— Kner, Denkschr. Akad. Wiss. Wien, VII, 1854, 260 (Barra do 



Rio Negro). 

 Plecostomus emarginatus Gunther, Catalogue, V, 1864, 233. — Eigenmann and 



Eigenmann, Proc. Cal. Acad. Sci., (2), I, 1888, 167; Occasional Papers Cal. 



Acad. Sci., I, 1890, 400 (Cudajas; Santarem; Manacapuru; Tonantins; Obidos; 



Fonteboa; Tabatinga; Hyavary; Sao Paulo; Goyaz) ; Proc. U. S. Nat. Mus., 



XIV, 1891, 40. — Eigenmann, Repts. Princeton Univ. Exp. Patagonia, III, 



1910, 406. 

 Hypostomus squalinum S( homburgk, Fishes Brit. Guiana, I, 1841, 142, pi. 3 (Rio 



Branco; Rio Negro; Rio Essequibo), 



