The intrinsic muscles of the syrinx fixed to the ends of the bronchial semi-rings; the edges of both mandibles perfectly smooth except for the presence of a small notch in the upper near the tip; the hinder part of the tarsus longitudinally bilaminated, the lamina; entire and smooth ; wing with nine primaries, the first and second nearly equal; bill long and slender; the longest secondaries reaching nearly or quite to the tip of the wing; a complete autumn and a partial spring moult; young not very dissimilar to the adult; tail of twelve feathers; rictal bristles present and fairly well developed; sexes alike or nearly so; tarsus slightly scutellated.
The Motacillidae comprise the Wagtails and Pipits, birds of wide distribution, and, in nearly all cases, migratory.
The Indian species of this family resemble each other very closely in structure, and there are few characters by which to divide them into genera. I shall content myself with making use of four genera, two of them being of large extent, and two restricted to a single species each.
The "Wagtails and Pipits are chiefly found on the ground; a few species have the habit of flying up into trees when disturbed. They feed entirely on insects, and their deportment is very graceful. They have no great power of song.
Key to the Genera.
A. Upper plumage neither streaked nor mottled, but plain.
a1. Middle pair of tail-feathers as long as the others, or longer………………..MOTACILLA, p. 285.
b1. Middle pair of tail-feathers abruptly shorter than the next, and of a markedly different colour………………..LIMONIDROMUS, p. 300.
B. Upper plumage streaked or mottled.
c1. Tips of tail-feathers rounded and of normal shape………………..ANTHUS, p. 301.
d1. Tips of tail-feathers sharply pointed………………..OREOCORYS, p. 313.