Cuckoo. A type of bird of which there are different variations, some of which, it is claimed, are identified by body size and others by color. Aldrovandi reports that, according to the bird catchers of Bologna, there are different sized cuckoo birds that are similar in color; and conversely, others which are of similar color even though they are different sizes.

Willughby gave the description of the most common cuckoo: the one that he described was eleven inches long from the point of the beak to the end of the tail. The upper part of the beak was slightly hooked, longer than the lower, and of a blackish brown on most of its length. The lower part was a whitish yellow. The tongue and the insides of its mouth were the color of saffron: the tongue was hard and transparent and the irises of the eyes were hazel. The openings of the nostrils were round, big, covered in feathers, and flared. This last trait, according to Willughby, is unique to the cuckoo, and distinguishes it from all other birds he had seen. The lower eyelid was large, with yellow eyelashes. This cuckoo had a white throat, chest, and stomach, with continuous, brown transversal lines more numerous around the throat and situated closer together. The edges of the feathers on the head were white and the rest of each feather was brown and there were one or two white patches on the head . The feathers on the back, the middle of the neck, and the large shoulder feathers were also brown in the center and whitish on the edges: in some there was a mix of red and brown. The under-parts of the cuckoo were the color of dead leaves. The large wing feathers of this bird were black and the outer edges of these feathers, with the exception of the outermost one, were speckled with red. On the inside edges of the outermost feathers there were long white patches. The tips of all the wing feathers were white, and the small wing feathers were the same color as the bird’s back feathers. Willughby did not describe the cuckoo’s tail, but according to Aldrovandi’s description of a second cuckoo, the tail is composed of ten feathers having some whitish spots, forming the shape of a heart, which are aesthetically pleasing; when the tail feathers are outstretched, all the tips are white like the inside edge, except the two in the middle. The legs and the claws are yellow and there are two claws in back, of which the inner claw is the smallest; the claws in front are joined together by a membrane until the first joint.

The cuckoo does not make a nest but steals the nests of other birds; it removes the eggs from the stolen nest, replaces them with its own, and leaves it: the cuckoo only lays one egg. The bird who owns the nest incubates the cuckoo’s egg, looking after the baby when it is born and feeds it until it is strong enough to fly. Before molting, the baby cuckoos have different colored plumage arranged in patches; they are quite beautiful. Generally, the cuckoo lays its egg in the nest of the brown warbler; it also takes over the nests of larks, finches, wagtails, etc. Willughby does not tell us if the cuckoos stay hidden and asleep during the winter in hollow trees, in rock holes, in the ground, etc., or if they migrate to warmer climates; however there are some people who claim to have heard cuckoos singing in hollow trees in the middle of winter when the air was balmy. The name of the bird comes from its call. See Bird.