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 tlie Passeres. But even 

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

 more or less trace of the more eonnuon arrangement, thus enabling us to decide that 

 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 trencliently differentiated, and intermediate forms may- 

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

 all three stages. The Buccouidte have non-oscinine wing-coverts, these being larger 



Fig. 204. — Lypomix torguata, double-banded puff-bird. 



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

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

 they are quite oscinine in size and number. 



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

 plumage, are also otherwise distinguishable from the Megalaiinida>, or barbels, 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 barbels. 

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

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

 species here illustrated, the double-b.anded puff-bird {Lypomix torqiiata). They are 

 small birds, the largest s]>ecies hardly so large as a robin, with a rather short, conical 



