Page:The Fauna of British India, including Ceylon and Burma (Birds Vol 1).djvu/176

138 l'''. Outer edges of primaries conspicuously parti-coloured.

l.4 Nostrils overhung by hairs, p. 286.

m4. Nostrils overhung by numerous small hairs; tail strongly graduated.

i5. Bill narrow; hind toe and claw equal, p. 289.

j5. Bill broad; hind claw shorter than hind toe, p. 293.

d. Wings longer, not so rounded and not fitting close to the body.

h'. Wing more than three times length of tarsus, p. 257.

i'. Winer less than three times length of tarsus.

g''. Tail more than three times length of tarsus, p. 258.

h''. Tail equal to twice lengtli of tarsus.. , p. 259.

C. Tail under 45 mm.

e. Bill as long as the head; curved downwards. , p. 255.

f. Bill half as long as the head; straight. . . ., p. 250.

Genus DRYONASTES Sharpe, 1883. The genus Dryonastes, of which D. ruficollis is the type, contains those Laughing-Thrushes which have the nostrils almost completely hidden by bristles, and in many respects show a similarity to the Corvidæ, from which, however, in others they are as widely divided as they are in their habits and nidification.

They are all noisy, gregarious birds, feeding principally on the ground but also on bushes, and they eat both insects, seeds and fruit.

Harington proposed to divide the birds of this genus into two genera on account of the varying degree of density in the plumes and bristles at the base of the bill and by the differences in the shape of the bill itself. To be consistent, however, one would have to make yet further genera, for if rufcollis differs in degree from cærulatits, so also galbanus differs to an equal extent from ruficollis. Under the circumstances it would seem wiser to keep them together, and this I do.

A. Chin and throat black.

a. Ear-coverts black D. rufcollis, p. 139.

b. Ear-coverts white.

a'. Back chestnut D. niichalis, p. 140.

b'. Back olive-brown D. chinensis, p. 141.

B. Chin and throat white.

c. Tail with no pale tip D. cærulatus cærulatus, p. 141.

d. Tail with pale tip.

c'. Ear-coverts white D. c. subcæsrulatus, p. 142.

d'. Ear-coverts brown D. c. kaurensis, p. 143.

C. Chin and throat chestnut-brown D. sannio, p. 144.

D. Chin black, throat yellow D. galbanus, p. 145.