PUFF-BIRDS. 



413 



much less numerous, forming fewer series than in the latter. He furthermore demon- 

 strated the 'perverse' situation of the middle coverts in the Passeres. But even 

 more interesting is his observation that the young birds in the first plumage show 

 more or less trace of the more common arran gement, thus enabling us to decide that 



O i ~ 



the latter is the generalized stage, while the ' oscinine ' arrangement is a specialization 

 of it. The oscinine or non-oscinine arrangement of the wing-coverts, therefore, can- 

 not be expected to be always trenchently differentiated, and intermediate forms may 

 occur, which he has termed sub-oscinine, and in fact our present super-family presents 

 all three stages. The Bucconidne have nou-oscinine wing-coverts, these being larger 



FIG. 204. Lypomix torquata, double-banded puff-bird. 



and numerous ; in the Galbulidas they are smaller and fewer, but not so much reduced 

 as in the Oscines, consequently sub-oscinine ; while in Ramphastidre, Megalaimidae, etc., 

 they are quite oscinine in size and number. 



The Bucconidse, or puff-birds, as they are called from their loose and puffy 

 plumage, are also otherwise distinguishable from the Megalaimidse, or barbets, by 

 having twelve tail-feathers, while the latter have only ten, and by their dull and 

 sombre coloration, as compared with the many and gaudy colors of the barbets. 

 Some of the puff-birds (the genus Monasa) are nearly uniform blackish slate, while 

 others are of a mottled rusty and dusky, with whitish markings, as, for instance, in the 

 species here illustrated, the double-banded puff-bird (Lypornix torquata). They are 

 small birds, the largest species hardly so large as a robin, with a rather short, conical 



