SOUTH AMERICAN NEMATOGNATHI. 421 



388, Hemiancistrus guacharote, 



Hypostomus guacharote Cuv. & Val. Hist. Nat. Poiss. xv, 508, 1840 



(Porto Kico). 

 ? Ancistrus guacharote Gill, Syn. Fish. Trinidad, W. I. 1858, 49 



(Trinidad). 

 Chcetostomus guacharote Giinther, v, 245, 1864 (copied); Jordan, 



Proc. U. S. Nat. Mus. 560, 1886 (name only). 

 Hemiancistrus guacharote Eigenm. & Eigenm. Proc. Cal. Acad. 2d 



Ser. ii, 43, 1889. 

 Habitat: Porto Kico; Trinidad. 



389, Hemiancistrus trinitatis, 



Ancistrus guacharote Gill, Syn. Fish. Trinidad, W. I. 49, 1858 



(Trinidad). 

 Chcetostomus trinitatis Giinther, v, 246, 1864 (copied); Jordan, Proc. 



U.S. Nat. Mus. 559, 1886 (name only). 

 Hemiancistrus trinitatis Eigenm. & Eigenm. 1. c. 

 Habitat: Trinidad. 



390, Hemiancistrus vittatus. 



Chcetostomus vittatus Steindachner, Flussfische Siidain. ii, 115, pl.ii, 



fig. 5, 1881 (Amazon). 

 Hemiancistrus vittatus Eigeum. & Eigenm. Proc. Cal. Acad. Sci. 2d 



Ser. ii, 44,1889 (KioTrombetas; Porto do Moz; Tajapuru; Obidos; 



Avary). 

 Habitat: Amazon from Tajapuru to Obidos. 



Rather short and heavy forward, the depth about 1J in 

 the width. Head short and high, its width at the oper- 

 cles one diameter less than its greatest length; surface of 

 the bones finely granular. Profile steep, convex; a low 

 median ridge from tip of snout to the occiput; occipital 

 bone roof-shaped in the young, slightly convex, with a 

 short median keel in the adult; superciliary edge raised, 

 the ridge less distinct in the adult. 



Margin of snout granular except at the tip. 



Orbit 2|-3i in the snout, 5-6J in the head, 2-2J in the 

 interorbital. 



Preopercle erectile, with numerous slender spines; 

 opercle fixed. 



A granular region between the gill-opening and the 

 mouth. Teeth small, numerous. Barbel large, as long 

 as the orbital diameter. 



