54 • BIRDS OF BRITISH GUIANA. 



Genu? PERCNOSTOLA Cab. & Hein. 



Percnostola Cabanis & Heine, Mus. Hein. ii. p. 10, 18-")9. Tj^pe P. rtifi- 

 frona (Gniel.). 



Fig. 2G. — Percnostola nijifrons. 



This genus is distinguished in having the head crested, the 

 feathers of the back long and disintegrated, and the absence of a 

 concealed dorsal patch. 



The bill is short and stout, the exposed culmen about two-thirds 

 the length of the tarsus. The wing rounded, the fourth, fifth, 

 sixth, seventh, and eighth primaries longest and subequal, the 

 third slightly shorter than the ninth. The tail is also rounded 

 and is about three-fourths the length of the wing. Coloration : 

 the male and female are quite different in colour. 



382. Percnostola rufifrons. 



('AYENNE Black-headed Ant-catch ek. 



Tardus rujjfrons Gmel. Syst. Nat. i. p. 825, 1789 (Cayenne). 

 Pyri(/lena finiehrh Cab. in Schomb. Keis. Guian. iii. p. 084, 1848; 



Salvin,"l])is, 1885, p. 429. 

 Percnosfolafunrhris Sclatev, Cat. B. Brit. Mus.xv. p. 273, 1890. 

 Percnoxlola rufifrons Eraboiu-ne & Chubb, B. S. Anier. i. p. 208, 



no. 2093, 1912. 



Adult male. General colour above and below dark slate-colour ; 

 upper Nving-coverts, including the bastard-wing, black narrowly 

 fringed with white at the tips of the feathers ; primary-coverts, 

 primary and secondary quills dark brown margined on the outer 

 edges vvith dark slate-colour ; tail similar to the back, with 

 indistinct dark narrow cross-bars; entire head, sides of face, neck 

 all round, and throat black ; under wing-coverts and quills below 

 pale brown ; lower aspect of tail blackish. 



Total length 1;">1 mm., exposed culmen 20, wing 73, tail 58, 

 tarsus 30. 



