The Zoologist — July, 1870. 2213 



trenchantly divided from white areas. The peculiar kind of mottling 

 exhibited by this species is so unusual as a condition of perfect 

 maturity, that the suspicion arises that the very highest state of 

 plumage is not yet known. 



Young. — Entirely similar in plumage to the bird as just described; 

 but the under parts white, scarcely relieved by mottling; and the 

 white extending far around on the sides of the neck, leaving only a 

 narrow median dorsal line black; the bill smaller than that of the 

 adult, and the tubercle wholly wanting, or very imperfectly developed ; 

 its place on the culmen being occupied by a soft skinny covering like 

 that on the nasal fossae. 



Specimens frequently occur in this condition. An understanding 

 of its precise import is somewhat complicated by the fact that, 

 although the tubercle is entirely wanting, and the bill otherwise 

 obviously undeveloped, the head is well provided with the whitish 

 setaceous feathers. Birds in such condition might be confounded, on 

 casual inspection, with S. pusillus. But more careful examination will 

 result in the observation that the bill is far too large, thick and heavy 

 to be that of pusillus ; that there is no conspicuous white patch on the 

 scapulars ; that the size of the whole bird exceeds that of pusillus : 

 which points, in connection with some others which might be 

 enumerated, will serve to distinguish the two species. Their rela- 

 tionships are dwelt upon more at length in the succeeding article. 



When old birds of this species are moulting, in the fall, the glossy 

 black of the fresh feathers on the back is interrupted with dull grayish 

 black patches, formed by the old feathers which have not yet been 

 renewed ; and the old worn primaries and secondaries are dull grayish, 

 fading almost into grayish white at their tips and along their edges. 

 A specimen in such a condition (No. 46,563, Smiths. Mus.), though 

 palpably an old bird, has no trace of a caruncle on the bill. 



It may not, perhaps, be exceeding due bounds to hint at the 

 possibility that the nodule on the bill may be temporary in character, 

 assumed after a certain age, at a certain season, and then lost, wholly 

 or in part, by absorption, to be again resumed at the same period of 

 the following year, probably during the season of reproduction. This 

 suggestion presents itself to the observer without straining on his part, 

 and, in fact, is rather forced upon his attention, after examination of 

 specimens, apparently adult, in which no trace of the tubercle is to be 

 found. The tubercle is in essential characteristics an extrinsic forma- 

 tion upon the bill, diflFering radically in its structure from the rest of 



