only member known of the genus, with a tail resembling that of the lyre-bird, the extravagantly long feathers being so narrow as to appear almost
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The Naturalist in La Plata.
like shafts destitute of webs. This tail appears to be purely ornamental.
This extreme variety in structure indicates a corresponding diversity in habits; and, assuming it to be a true doctrine that habits vary first and structure afterwards, anyone might infer from a study of their forms alone that these birds possess a singular plasticity, or tendency to vary, in their habits--or, in other words, that they are exceptionally intelligent; and that such a conclusion would be right I believe a study of their habits will serve to show.
The same species is often found to differ in its manner of life in different localities. Some species of Xenops and Magarornis, like woodpeckers, climb vertically on tree-trunks in search of insect prey, but also, like tits, explore the smaller twigs and foliage at the extremity of the branches; so that the whole tree, from its root to its topmost foliage, is hunted over by them. The Sclerurus, although an inhabitant of the darkest forest, and provided with sharply-curved claws, never seeks its food on trees, but exclusively on the ground, among the decaying fallen leaves; but, strangely enough, when alarmed it flies to the trunk of the nearest tree, to which it clings in a vertical position, and, remaining silent and motionless, escapes observation by means of its dark protective colour. The Drymornis, a large bird, with feet and tail like a woodpecker, climbs on tree-trunks to seek its food; but also possesses the widely-different habit of resorting to the open plain, especially after a shower, to feed on larvae and earthworms, extracting them from a depth of three
The Woodkewer Family. 241
or four inches beneath the surface with its immense curved probing beak.