6E0THLYPIS. 



Genus GEOTHLYPIS Cab. 



409 



Geotlilypis Cabanis, Arch, fiir Naturg. 1847, pp. 316, 349. Type 

 G. trichas (Linn.). 



rig. 156. — To show the form of the bill and nostrils. 



The predominating colour in this genus is yellow, which varies 

 in its brightness among the species. The bill is pointed, the width 

 at the base being less than half the length of the exposed culmen. 

 The wing is rounded, the third, fourth, and fifth primaries are 

 longest, the second about equal to the sixth, and the first about 

 equal to the eighth. The tail is rounded at the tip and nearly 

 equal in length to the wing. The tarsus is about twice the length 

 of the exposed culmen. Coloration : male and female similar. 



606. Geothlypis sequinoctialis. 



Equinoctial Warbler. 



Motacilla mquinoctialis Gmel. Syst. Nat. i. p. 972, 1789 (Cayenne). 

 Geoihlypis velata (nee Vieill.) Cab. in Sohomb. Eeis. Guian. iii. p. 666, 



1848. 

 GeotMypis cequinoctialis Salvin, Ibis, 1885, p. 203 (Yaruani River) ; 



Sharpe, Cat. B. Brit. Mus. x. p. 360, pi. ix. fig. 7, 1885 (Demerara) ; 



Brabom-ne & Chubb, B. S. Amer. i. p. 856, no. 3641, 1912. 



Adult male. Crown of head pale slate-grey ; entire back, wings, 

 and tail yellowish green ; inner webs of flight-quills dark brown ; 

 base of forehead, lores, cheeks, and ear-coverts black ; throat, 

 breast, abdomen, under tail-coverts, and under wing-coverts bright 

 yellow, rather darker on the sides of the body ; under surface of 

 quills dark brown ; lower aspect of tail yellowish green. 



Total length 133 mm., exposed culmen 11, wing 61, tail 56, 

 tarsus 21. 



The specimen on which the description is based was collected at 

 Bartica in 1911. 



Adult female. Differs from the adult male in being less bright 

 in colour and the absence of the black on the base of the forehead, 

 lores, cheeks, and ear-coverts. Wing 55 mm. 



