Page:The Fauna of British India, including Ceylon and Burma (Birds Vol 1).djvu/52

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20
CORVIDÆ.
d’.
Graduation of tail more than length of tarsus; rictal bristles moderate or obsolete.
c’’.
Nostrils nearer edge of culmen than to lower edge of upper mandible.
c’’’.
Bill about half length of head, deep and notched
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Garrulus, p. 59.
d’’’.
Bill about same length as head, slender and not notched
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Nucifraga, p. 66.
d’’.
Nostrils nearer lower edge of upper mandible than to culmen.
e’’’.
Wings long, falling short of the tip of the tail by less than length of tarsus
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Pyrrhocorax, p. 69.
f’’’.
Wings short, falling short of the tip of the tail by more than length of tarsus
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Podoces, p. 71.


Genus CORVUS Linn., 1766.

The genus Corvus contains the Ravens, Crows, Rooks and Jackdaws. Seven species are found in India, several of which are divisible into well-marked geographical races, some of which were ranked by Gates as species whilst others equally easily differentiated were altogether ignored. Of the seven species some are widely distributed and well known to all, and others are confined to the Himalayas and the north-west portion of the Empire.

Corvus has the plumage black throughout or nearly throughout, and may be recognized by the position of the nostrils, which are placed far forward, about one-third the length of the bill from the forehead, and are entirely concealed from view by a multitude of very stiff, straight bristles that reach the middle of the bill. In these characters this genus agrees with the Magpies; but the latter may be separated by the length of the tail, which is very much longer than the wing, and the shape of the first primary, which is figured on p. 37.

The Crows are with two exceptions resident, the other two being only winter visitors.

The Rook forms a partial exception to the general characters given above for determining Corvus. Up to nine months of age it has the ordinary stiff bristles over the nostrils, but at that age it casts them all off, as well as the feathers on the front part of the head. Its appearance in this state is well depicted in the figure of the head given on p. 31.

Key to Species.

A.
Size large, wing always over 380 mm.
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C. corax, p. 21.
B.
Size smaller, wing always under 380 mm.
a.
Crown and neck concolorous or nearly so.
a’.
Lower plumage with little gloss, and this blue or green; bill stout, face feathered in adults.