The birds in this section are characterised by the fact that the upper mandible is provided with a distinct notch in its lower margin near the tip (fig. 345, B). They all feed chiefly upon insects. This sub-order includes the Shrikes (Laniidae), the Fly-catchers (Muscicapidae), the Thrushes (Meru/idae), the Tits (Paridae), and the Warblers (Sylviadae).
The Muscicapidae, including the numerous species of Flycatchers, are the most insectivorous of the Dentirostres. The gape is wide and bordered with bristles, and the legs are short and weak. They are mostly sedentary, catching their prey from a fixed point.
Fig. 346. - Head of the common Bullfinch (Pyrrhula vulgaris), showing the conirostral beak.
The Shrikes are highly predaceous birds, which in many respects make a close approach to the true Birds of Prey. They feed, however, mostly upon worms and insects, and only occasionally destroy small birds or mice.
The great family of the Thrushes (Merulidae) comprises not only the true Thrushes, Fieldfares, and Blackbirds, but a number of exotic forms, of which the most familiar are the Orioles, so well known for their brilliant plumage and their beautifully-constructed nests.
In the Sylviadae, amongst other forms, are the Wagtails (Motacillinae) and the Pipits (Anthus), the Titmice, Robins, Hedge-sparrow, Stonechat, Redstarts, and other well-known British birds. The Titmice (Panda) are often placed in the sub-order of the Conirostres. The Nightingale also belongs to this family.
The members of this sub-order are characterised by the possession of a long and slender beak, gradually tapering to a point (fig. 345, A). The toes are very long and slender, the hind-toe or hallux especially so. Most of the Tenuirostral birds live upon insects, and some of these present a near resemblance in many of their characters to the Dentirostres, but it is asserted that some live partially or wholly on the juices of flowers.
The chief families of the Tenuirostres are the Creepers (Certhidae), the Honey - eaters (Meliphagidae), the Hummingbirds (Trochilidae), the Sun-birds (Promeropidae), and the Hoopoes (Upupidae), of which only the Creepers and Humming-birds need any further notice.
The family Certhidae includes several familiar British birds, such as the little brown Creeper (Certhia familiaris), the Nuthatch (Sitta Eiiropaea), and the Wrens (Troglodytes). With these are a number of exotic forms, of which the singular Lyre-birds of Australia are the most remarkable.
The family of the Trockitidae, or Humming-birds, includes the most fragile and brightly coloured of all the birds, some not weighing more than twenty grains when alive, and many exhibiting the most brilliant play of metallic colours. The Humming-birds are pre-eminently South American, but extend northwards as far even as the southern portions of Canada. The bill is always very long and slender, as are the toes also. The tongue is bifid and tubular, and appears to be used either to catch insects within the corollas of flowers, or to suck up the juices of the flowers themselves. The plumage of the males is always brilliant, with metallic reflections, that of the females generally sombre. The legs are short and weak, but the wings are proportionately very long, and the flight is exceedingly rapid.
The Sun-birds represent in the Old World the Humming-birds of the western hemisphere, and the Australian Honey-eaters show also many points of resemblance to the Trochilidae.