Order VII. HEMIPODII.
The Hemipodii, or Bustard-Quails, are an Order of small birds which in general appearance closely resemble true Quails but, so far as our Indian birds are concerned, can always be identified at a glance by the fact that they have only three toes, the hallux, or hind-toe being absent. According to some naturalists two genera are contained in one family, Turnicidae: i.e., the Three-Toed Bustard-Quails of the genus Turnix, and the Plain Wanderers with four toes of the genus Pedionimus, which are confined to Australia. Other systematists, however, put this latter genus in a separate family, though, as it is not represented in Asia, this point does not interest us.
The nearest relatives of the Bustard-Quails are to be found amongst the Gallinae or Game-birds, the Pterocletes or Sand-Grouse, and the two Families Rallidae (Rails) and Charadriidae (Plovers).
The principal anatomical difference between the Gallinae and the Pterocletes and the present Order lies in the formation of the vertebrae. In the two former Orders the last cervical and anterior dorsals are all anchylosed in fully adult birds, whereas in the Bustard-Quail they are free ; in the two former, also, the last dorsal vertebra is united with the lumbar vertebrae to form the sacrum.
In the Gallinae the sternum has two notches and the same with Pterocletes, though in the latter the second notch may be much reduced; in the Hemipodii there is one deep long notch only on each side of the posterior border, and the episternal process is partially perforated to receive the inner ends of the coracoids.
The palate is schizognathous, as in the Gallinae, but the palatines, pterygoids and basiterygoids are more like those of the Plovers.
The nasals are schizorhinal.
The muscles of the thigh are Galline except that the accessory femoro-caudal is absent. In our genus Turnix, the deep plantar tendons unite, as in other birds with but three toes, and then the combined tendons again split up to supply the three toes.
In other respects the Bustard-Quails resemble the Game-birds; the young are hatched covered with down and can run and feed themselves as soon as they leave the nest.
The eggs are practically invariably four in number, and are somewhat conical, being laid in the nest in the same manner, point to point, as the Plovers lay their eggs.
The females in this Order are larger than the males, often more richly coloured and are polyandrous, leaving the duties of incuba¬tion and rearing of the young to the males.