OHALCOSTETHA. 345 



given rise to the belief that a seasonal change takes place in the 

 adult. 



The young birds of both sexes resemble the adult female up to 

 the first autumn moult. The males then commence to assume the 

 colours of the adult and the change is effected very slowly and 

 probably extends over a whole year. 



The Indian Sun-birds may be conveniently divided into two 

 subfamilies. 



Sexes different ; plumage of male in part 



metallic ; bill slender ; nest pensile. Nectariniince, p. 345. 

 Sexes alike ; plumage non-metallic ; bill 



large ; nest cup-shaped, attached by 



a portion of the rim to a broad 



leaf Arachnotherince, p. 368. 



Subfamily NECTARINIINCE. 



The Sun-birds of this subfamily are characterized by a slender 

 body and an attenuated bill ; by the sexes being different, and by 

 the males having bright metallic colours in their plumage, the 

 females being of a dull green or yellow colour. 



Key to the Genera. 



a. Covering-membrane of nostril feathered. CHALCOSTETHA, p. 345. 



b. Covering-membrane of nostril bare. 



a'. Lower mandible of bill distinctly 



curved downwards. 

 a". Males with middle tail-feathers 

 elongated ; rump yellow ; females 



with lower plumage green ^ETHOPYGA, p. 346. 



b' 1 . Both sexes with short, rounded 



tails ; females yellow beneath . . ARACHNECHTHRA, p. 357. 

 b'. Lower mandible of bill straight or 



nearly so ANTHOTHREPTES, p. 3(>">. 



Genus CHALCOSTETHA, Cabanis, 1850. 



The genus Chalcostetha contains a single species of Sun-bird, 

 which may be recognized by the covering-membrane of the nostril 

 being completely plumed and by the tail being of considerable 

 length and well graduated. The bill is slender and the lower 

 mandible is nearly straight. 



881. Chalcostetha pectoralis. Mnklot's Sun-in,-'!. 



Nectarinia pectoralis, Temm. PI. Col. pi. 138, fig. 3 (1823). 

 Nectarinia insignia. Jard. Naturalist's Libr.. Sun-bird*, p. 274 



(1848). 



Nectarinia insignis, Gould, P. Z. S. 1865, p. 663. 

 Chalcostetha insignis (Jard.), Wuldcn, Ibis, 1870, p. 44; Hume,S.F. 



