Cephalopyrus Bonap., Jerdon, B. of Ind., ii, p. 267 (1864).
Type, C. flammiceps Burton,
This genus contains but one species which is apparently very closely allied to the preceding but the wing is proportionately longer and more pointed, with a minute first primary and the tail is short and square.
Oates thought it probable that Cephalopyrus has a Spring moult, or at any rate a partial one, but that the material at his disposal was insufficient to prove this.
The extraordinary nidification of this bird, blue eggs laid in holes in trees, at once makes one very doubtful as to whether it can possibly be placed with the Regulidae and it may have to be removed therefrom, either to another family or, more probably, to a family, Cephalopyridae, by itself. Certainly, in so far as its nidification is concerned it shows no affinity with any other Oriental bird with which I am acquainted.
The egg is like that of the Suthoras and so may be said to form a link with the Tits through the Paradoxornithidae, but those birds make very Panurus-like nests and do not lay their eggs high up in tiny holes in trees.
For the present I retain it, though with many misgivings, in this Family.