on the Genus Coereba. 507 



CCEREBA GUIANENSIS. 



Certhiula (juianensis Cab. Mus. Hein. i. p. 97 (1851) ; 

 Sclater, Cat. Am. Birds, 1862, p. 53. 



Coereba guianensis Berlepscli & Hartert, Nov. Zool. vol. ix. 

 p. 17 (1902). 



Coereba guianensis Hellmayr, Nov. Zool. vol. xii. p. 272 

 (1905). 



Hab. Highlands of British Guiana (Roraima, Bartica 

 Grove, Merume Mts., Camacusa) ; North Brazil, Upper 

 Rio Negro (Marabitanas, Cobati) ; South Venezuela, Rio 

 Suapure, Rio Caura. 



Specimens examined. Seventeen adult males and females 

 from British Guiana (Coll. Brit. Mus.), and twelve from 

 Rivers Suapure and Caura, Venezuela (Coll. Rothschildi) , 



This is a very distinct species and any series from the 

 above-mentioned localities is recognizable at the merest 

 glance from typical C. chloro])yga with which one might 

 have expected it to be closely allied. 



Upper parts. Pileum pure black ; mantle, neck, and 

 scapulars dark brownish black, barely distinguishable from 

 pileum and totally distinct from the ashy-brown mantle of 

 C. chloropyga ; rump with a very conspicuous broad band 

 of bright and pure yellow, but not so rich as in C. luteola ; no 

 ■wing-spot. 



Under parts. The yellow of these is deeper and richer 

 than in true C. luteola and very similar, if not identical, 

 with that seen in Trinidad birds. Throat-patch nearly 

 identical with that of true C. luteola and C. chluropyga. 



To sum up, C. guianensis is practically similar to C. luteola, 

 but is without any wing-spot. 



A glance at a map will shew that the distribution of this 

 species corresponds to a well-defined and more or less 

 isolated geological area characterized by a system of rocks 

 of extreme antiquity — an area, be it said, which at no remote 

 period of time probably stood out as a prominent insular 

 mass. 



