THERMOCHALCIS. 365 



Keij to the Species. 



A. Smaller, wing- less than 150 mm T. caiipnnpnals, p. .SGo. 



B. Larger, wing more than 150 mm T. rnjlcervix, p. 3GG. 



230. Tliermoclialcis cayennensis. 

 Cayenne Xight-Haavk. 



Capri midgus cayennensis Gmel. Syst. Xat. i. p. 1031, 17S9 (Cayenne) ; 



Cab. in Schomb. Keis. Guian. iii. p. 710, lS-18. 

 Stenopsis cai/ennensis Salvin. Ibis, 1SS5, p. 439 (^Meritme ^Its., 



Eoraima! 3500 to 40oO ft.) ; Hartert, Cat. B: Brit. Mus. xvi. p. 583, 



1892 (Aunai) ; Brabom-ne & Chubb, B. S. Amer. i. p. 101, no. 951, 



1912. 



AJuU male. Dark brown or blackis;h above Avitli oreA' mot f lings 

 and vermiculutions : sca[)ulars black broadly fringed with white or 

 buff; upper wing-coverts mostly tipped with white; outer priniarv- 

 quills banded with white, the inner ones spotted with white on 

 the inner webs, the secondaries similar and margined with white 

 at the tips ; middle tail-feathers like the back but more coarsely 

 marked, outer feathers for the most part white margined and 

 barred in the middle portion with dark brown ; feathers of the 

 crown centred with black and sometimes margined with rufous ; 

 a ])ale rufous collar on the hind-neck ; sides of face, throat, a 1 'do- 

 men, and under tail-coverts white ; sides of throat and breast buff 

 M'ith an admixture of white ; under wing-coverts dark brown with 

 more or less white intermixed. 



Total length 210 mm., cnlmen 11, wing 143, tail 114. tarsus 15. 



Adult fei)iale. Differs from the adult male in being much darker 

 and in the almost entire absence of white in the jdumage. The 

 white pattern of the male is re})laceil byrulbus, to some extent, in 

 the femab'. 



Total length 200 mm., culmen 11, wing 156, tail 107, tarsus 14. 



The birds from which the descriptions are taken were collected 

 on the Ituribisi River, 



Breediug-season. Unknown in British Gniana. 



I^est. Unrecorded in Biitisli Guiana. 



Eugs. Uudescribed from Briti.'>h Gniana. 



liaiuje in British (juio.na. Monnt Koraima, Ituribir*! Hiver 

 (MrCoiuiell rollection) ; Mount Koraima, I\Ieriime ^lountains, 

 Annai (//. 11 hiiidg). 



Ej-traliinitid Itange. Nortii Brazil, Venezuela, Colond)ia. 



Jlidnts. ^chombnrgk states (Ueis. (Juian. iii. [». 710) that he 



