The chaffinch is first heard before the end of February. He pairs early in March, and in April begins to build. The nest is placed in a shrub or tree, in a cleft, or on a horizontal branch. An apple, pear, or cherry tree in an orchard is a favourite site; but any tree, from an evergreen in a garden to the largest oak or elm, may be selected, and the nest may be at any height from the ground from half a dozen to fifty feet. It is a very beautiful structure, formed outwardly of lichen, moss, and dry grass, compactly woven together, and mixed with cobwebs; the cup-shaped inside is lined with hair, vegetable down, and feathers. In most cases the outer portion of the nest is composed of materials that give it a close resemblance to the tree it is built on. Thus, on an oak or apple tree overgrown with grey lichen, or on a silver birch, the framework is chiefly composed of lichen; but in deep green bushes evergreen moss is used. The nest is built by the female, but the male assists in collecting and bringing materials. A fortnight, or longer, is taken to complete this elaborate nest; but from the beginning, and even before the nest is begun, the birds exhibit the greatest excitement and distress if the chosen tree is approached, flying round and flitting from branch to branch, incessantly uttering their well-known alarm-notes, usually spelt _pink-pink_ or _spink-spink_, a clear, penetrating sound, slightly metallic in character; also another sound, a lower and somewhat harsh note of anxiety. The eggs are four or five in number, of a pale bluish green, spotted and blotched with dull purplish brown. The young are fed on caterpillars and small insects. The adults, too, subsist chiefly on insects in summer, seeking for them on the ground, and sometimes capturing them in the air, like the flycatcher.