“Some cloudy morning early in the month, you will hear a new call. At first it may suggest the coo-oo-oo of the Mourning Dove, then the drumming of the Flicker, but after waiting for a moment you realize that it is neither. The first sound is like that made by clicking the tongue rapidly against the roof of the mouth; the second sounds like cow-cow-cow-cow-cow repeated in quick succession. By this you will know that the _Yellow-billed Cuckoo_ has come. “You will be disappointed when first you see the bird itself, for it does not in the least resemble the bird of the English poets, who lives in Cuckoo clocks and bobs out to tell the hours. Neither is it a lazy bird who refuses to build a nest and leaves its eggs to the care of others like the Cowbird. “This Yellow-billed Cuckoo is a slender bird cloaked in brownish gray, of a soft hue and with a light belly. The tail-feathers are tipped with white, so that, as you look at the bird from below, it shows large white spots. This Cuckoo takes its name because the lower part of its bill is yellow, but you will scarcely notice this when he is in the trees, where he spends the greater part of his time in searching for insects and caterpillars, which are his favourite food. [Illustration: YELLOW-BILLED CUCKOO] “The nest is a shallow, rather shiftless sort of an affair, and very often has so little lining that if the vine or bush in which it is placed tips a little, the pale blue eggs are in danger of rolling out. What the Cuckoos lack in housekeeping thrift they make up as destroyers of harmful insects, and here it has helped to keep the old orchard alive by tearing apart the nests of the tent-caterpillar and eating the inhabitants. These mischievous caterpillars used to be content to live in the wild cherry trees that line the roads and old pastures. People cut these down in consequence, so after a time the caterpillar found that apple trees were quite as much to his taste and seized upon the orchards. Then comes Master Cuckoo, and wherever the tent worms are, there we find him also. So many has he been known to devour that one of the Wise Men, upon examining the stomach of a Cuckoo that had been killed, found it lined with a sort of felt made from the hairs of the caterpillars. “So, if you hear the harsh call near by, be very glad; the sound may not please the ear, but the bird is a pleasure to the sight as he slips away silently through the trees to do work for us that we cannot do as well.