I have already referred to this genus when dealing with AEgithina.
It contains a large number of species of bright plumage, principally green, which extend from Ceylon, through India, Burma, (Siam etc. to Western China and through the Malay Peninsula to the islands.
It is represented in India by six species, some of which have numerous geographical races and are spread over a very wide area.
In this genus the bill is slender and curved and about as long as the head, the tip is notched and the nostrils are oval; the rictal bristles are weak ; the frontal feathers are advanced up to the nostrils; the wings are rounded, but are less so and longer than in the more typically Timaliine birds; the tarsi are very short, resembling in this respect the Pycnonotidae.
Key to Species and Subspecies.
A. Forehead rich yellow-orange.
a. Chin and throat bright blue. [p. 346.
a1. A. yellow collar round blue throat .... C. aurifrons aurifrons,
b1. Yellow collar absent or obsolete C. a. inornata, p. 349.
b. Chin and throat black C. a. davidsoni, p. 348.
B. Forehead greenish or yellowish.
c. Abdomen orange C. hardwickii, p. 349.
d. Abdomen green.
c1. Outer webs of primaries blue C. icterocephala chloro-
d1.. Outer webs of primaries green. [cephala, p. 350.
a2.. A bright patch of colour on wing-coverts.
a3. Moustachial streak a mere short,
narrow line C. viridis zosterops,
b3 Moustachial streak broad and [p. 351.
occupying the whole cheek .... C. jerdoni, p. 352.
b2. No bright patch of colour on wing-
coverts C cyanopogon, p. 353.