The genus Niltava contains three species of Flycatchers remarkable for the brilliant plumage of the males. The sexes differ in colour, but both may be recognized by the presence of a bright spot or mark on the side of the neck. Cyornis oatesi approaches these birds in having some bright blue on the side of the neck, but the patch is of a different character, being connected with the nape and forming a band rather than a spot. This bright mark is moreover absent in the female.
The Niltavas frequent thick jungle and are less typical in their habits than the species of Cyornis, and they are said to eat berries. They appear to be resident on the Himalayas. Mr. Cripps, however, states that N. sundara and N. macgrigoriae are seasonal visitors to Dibrugarh in Assam, but he omits to stale at what season they visit that district.
In Niltava the bill is somewhat compressed laterally and narrow, and the base is covered by a multitude of dense plumelets, which conceal the nostrils; the rictal bristles are moderate in number and in length; the first primary is large, being quite half the length of the second, and the tail is rounded.
Key to the Species.
a. Wing 4 inches or longer………………….N. grandis, p. 40.
b. Wing not much exceeding 3 inches or less.
a1. Under wing-coverts and axillaries chest-nut or buff………………….N. sundara, p. 41.
b. Under wing-coverts and axillaries white or ashy white………………….N. macgrigoriae, p. 42.