This subfamily, which formerly Oates placed in his Crateropodidae, is at once separated from that family by the fact that the young are all squamated, though they show a certain superficial resemblance to it in their long legs and short tails.
Since Oates wrote the Avifauna we have learnt much about the young of many more species than was known in his time, a fact doubtless due to his own recognition of the importance of this point. B. major major (Cardew), B. major albiventris (Howard Campbell), Heteroxenicus nipalensis (Baker), Hodgsonius Larvivora (Osmaston) are all known to have young of true Thrush type and it is now possible to place them in a position to which their habits and nidification also entitle them.
The bill is slender and about half the length of the head; the rictal bristles vary from small and weak in Larvivora to well-developed in Brachypteryx. The wings are short and rounded, the tail short or very short; the tarsi long, but more slender than in the Timaliidae. They are not gregarious.
Key to Genera.
A. Tail but little graduated or nearly square,
outer feathers tailing; short of tip of tail by less than half the length of tarsus.
a. Tail not less than twice the length of tarsus.
a1. Second primary much shorter than
longest secondaries Brachypteryx, p. 9,
b1. Second primary equal to, or exceeding,
secondaries Larvivora, p. 12.
b. Tail much shorter than twice the length
of tarsus Heteroxenicus, p. 10.
B. Tail greatly graduated, outer feathers falling
short of tip of tail by as much as the length
of tarsus Hodgsonius, p. 21.