NATURAL SCIENCES OF PHILADELPHIA. 55 



yellow nuchal crescent, and of the yellow at the base of the bill are some of 

 the features that distinguish hoth sexes from the C. Jiaviventris. 



44. Melanekpes fokmicivorus (Sw.) Bp. 



Exceedingly abundant, being the commonest Woodpecker, not even except- 

 ing P. Harrisii. Resident. Found in all situations. 



The tongue of this Woodpecker is rather brushed at the tip, like that of a 

 Sphyrapicus, than barbed, as in Picas, etc. Si ill it is exceedingly protruda- 

 ble, the hyoid bone being well developed. 



This species presents variations in the color of the iris rarely equalled. In 

 a great many individuals the iris is pure white, and so it is usually described. 

 But this is not the color in even a majority of instances, for this white is 

 tinged with various colors, red, blue, yellow or brown. A greater or less 

 admixture of red gives every shade from a clear rose pink to the most deli- 

 cate creamy white, and these tints are usual in adult spring birds of both 

 sexes. Varying degrees of yellowish or ochraceous are by no means rare. 

 Young birds are rarely found with pure white irides, for the color is usually 

 obscnred by a greater or less amount of blue or grey, producing a bluish grey 

 or a " milk white " tint. Rarely an individual is found with dark brown 

 irides. The latter seems to be purely accidental ; the admixture of blue to 

 denote immaturity, and the reddish tinge to indicate high spring maturity, in 

 each case quite independently of sex. 



The moult, which commences in July, continues for an unusually long pe- 

 riod, until November, at least in some instances. 



Adult birds are very constant both in size and plumage, but, at the same 

 time there is an immense variation in the length and stoutness of the bill in 

 different individuals. The black of the breast, and the lemon yellow on the 

 jugulum have often a few isolated red feathers among them. Some few spe- 

 cimens have white tips and inner borders of the secondaries, but this is un- 

 usual. The pileum of young birds has often a bronzy tint, not seen iu the 

 adult. 



ASYNDESMUS Coues, nov. gen. 



Generic Characters. Bill as long as the head, rather longer than the tarsus, 

 as high as broad at the base, terminally compressed, somewhat decurved ; 

 almost colaptine in general aspect. Culmen much curved, tips of bill acute, 

 gonys straight, lateral outline of bill decidedly concave, lateral bevelling 

 scarcely appreciable, lateral ridge distinct, superior and inferior ridges but 

 slightly developed. Wings very long, when folded reaching to near the end 

 of the long tail ; fourth quill longest, third and fifth about equal to each other 

 and shorter than the second. Inner anterior claw reaching but little beyond 

 the base of the outer claw. Feathers of the under parts and of a nuchal col- 

 lar with the fibres on their terminal portion disconnected, loosened, enlarged 

 in calibre, stiffened, almost bristle-like, with a peculiar glistening silicious 

 hardness, destitute of fibrilhe whereby to interlock. Dorsal plumage imbri- 

 cated, with an intense metallic lustre. 



Type. Picas torquatus Wilson. 



The bill of this genus is quite peculiar, approaching that of Colaptes in its 

 length, convexity of culmen, acute tip, and slightly bevelled sides ; and re- 

 sembling that of Melanerpes in its sharply defined lateral ridge. The nasal* 

 plumuli are long and bristly but not dense. The length of the wing is ex- 

 cessive, and the proportions of the primaries peculiar. The most essential 

 feature is found in the unusual texture of the feathers of the under parts 

 and nuchal collar, which has thus been described : " The fibres of the feath- 

 ers are longer than usual and remarkably stiff. Those on the terminal third 

 of each feather are of the usual character at the base, or provided with fibril- 

 lar, those of opposite sides interlocking as in feathers generally. The termi- 

 nal portion, however, of the stem of the fibre is much enlarged and expanded 



1866] 



