112 



AVIFAUNA OF LAYSAN, ETC. 



Key to the adult birds of the Genus Orcomyza. 



A. Plumage red O.flammea. 



B. Plumage not red, 



a. Bill short and somewhat stout, tail shorter. 



a\ Beneath whitish, ashy on the flanks, no green on breast 0. bairdi. 



b\ Beneath greenish °- mana - 



b. Bill longer and slenderer, tail longer. 



c x . Yellowish green above. 



a\ Head uniform yellowish, not perceptibly different from the back ....(). parva. 



b\ Forehead yellow, and quite different from the greenish back O. montana. 



d l . Olive-green above. 



c\ Broad dusky loral mark; bill stronger; colour deeper olive above, more 



golden beneath °- maculata. 



d\ Loral mark smaller; hill more slender; more greenish above, paler yellow 



beneath °- newtoni. 



Immature birds of these species are extremely alike, and in some cases not distinguishable, 

 or hardly so, without knowing the locality whence they came, although the males are always 

 easy to distinguish. The young of O. mana and 0. bairdi much resemble each other, but 

 are very different from those of the other species ; the young of 0. parva are the smallest, 

 those of 0. maculata have a more conical bill, and those of O.flammea have generally a 

 somewhat different and more brownish colour than all the others. 



