The strength of cobweb is proved by the fact that many of the birds that build hanging nests use it as cement to attach them to the supports from which they are suspended. The Indian white-eye (Zosterops palbebrosa) fixes its tiny oriole-like nest to the supporting branches, not by fibres, but by cobweb. In the same way the yellow-eyed babbler (Pyctorhis sinensis), whose nest is shaped like an inverted cone, attaches this by cobweb to the stems of the crop in which it is situated.
The common honeysucker (Arachnechthra asiatica), whose nest looks like a tangle of dried twigs and other rubbish, uses much cobweb in the construction thereof. The little nursery is suspended by means of cobweb from some projecting branch of a bush, and the various materials which compose it are stuck together with spider’s web; but in this case some sticky resinous substance is usually used in addition to the cobweb.
The tailor-bird (Orthotomous sutorius) always uses cobweb to draw together the edges of the leaf or leaves that compose its nest. Having made a series of punctures along the edges of the leaf to be utilised, it procures some cobweb, and, having attached it to one edge of the leaf, carries the strand across to the other edge and, before attaching it to this, pulls it so tightly as to draw the two edges together. When the nest has taken its final shape the bird strengthens the first attenuated strands of cobweb by adding more cobweb or some threads of cotton.
Many birds which weave their nests plaster the exterior more or less thickly with cobweb so as to add strength to the structure.
It would be wearisome to detail all the kinds of nest into the composition of which cobweb enters. Sufficient has been said to show that this very useful substance is the favourite cement of bird masons.
XXXII
INDIAN FLY-CATCHERS
There exist in the Indian Empire no fewer than fifty-one species of fly-catcher. This fact speaks volumes for the wealth of both the bird and the insect population of India. Fly-catchers are little birds that feed exclusively on insects, which they secure on the wing. Their habit is to take up a strategic position on some perch, usually the bare branch of a tree, whence they make sallies into the air after their quarry. Having secured the object of their sortie—and this they never fail to do—they return to their perch. A fly-catcher will sometimes make over a hundred of these little flights in the course of an hour; the appetite of an insectivorous bird appears to be insatiable. All fly-catchers obtain their food in this manner, but all birds which behave thus are not members of the fly-catcher family. As fly-catchers are characterised by rather weak legs, and, in consequence, do not often descend to the ground, they are of necessity confined to parts of the country well supplied with trees. Thus it comes to pass that the great majority of fly-catchers are found only in well-wooded hill tracts. Four or five species, however, occur commonly in the plains. With two of these—the glorious paradise fly-catchers (Terpsiphone) and the very elegant fan-tail fly-catchers (Rhipidura)—I have dealt in my former books. I therefore propose to confine myself to some of the many other species. Of these last, the brown fly-catcher (Alseonax latirostris) is the one most frequently met with in the plains. This is the most inornate of all the fly-catchers. As its name implies, brown is its prevailing hue. Its lower parts are, indeed, whitish, and there is an inconspicuous ring of white feathers round the eye, but everything else about it is earthy brown. It is the kind of bird the casual observer is likely to pass over, or, if he does happen to observe it, he probably sets it down as one of the scores of warblers that visit India in the cold weather. It is only when the bird makes a sudden dash into the air after an insect that one realises that it is a fly-catcher. The brown fly-catcher is an Ishmaelite. It seems never to remain for long in one place, and, although it may be seen at all times of the year, its nest does not appear ever to have been found in this country.
A more ornamental fly-catcher which occasionally visits the plains is the grey-headed fly-catcher (Culicapa ceylonensis). In this species the head, neck, and breast are ash-coloured, the wings and tail are dark brown, the back greenish yellow, and the lower parts dull yellow. This fly-catcher is common both in the Nilgiris and the Himalayas. It has the usual habits of the family. Like the majority of them it is no songster, although it frequently emits a cheeping note. Its nest is a very beautiful structure, a ball of moss which is attached to a moss-covered tree or rock, more often than not near a mountain stream.
Fly-catchers usually nidificate in the neighbourhood of water, because that element favours the existence of their insect food.
Siphia parva—the European red-breasted fly-catcher—is a species which visits the plains of India in the cold weather, but not many individuals penetrate so far south as Madras. This bird is easily recognised, since the cock bears a strong likeness to the familiar English robin red-breast. I may here mention that an allied species—the Indian red-breasted fly-catcher, S. hyperythra—summers in Kashmir and winters in Ceylon, but, curiously enough, it has not been recorded from the plains of India. It would thus seem to fly from Kashmir to Ceylon in a single night. Even so, it would be very extraordinary if an occasional individual did not fail to perform the whole journey in so short a space of time; therefore, this species should be watched for in South India in spring and autumn. It is easily distinguished from allied species by a black band which surrounds the red breast and abdomen.