[12] The popular name of this bird is the _Umbrella Bird_. On its head it bears a crest, different from that of any other bird. It is formed of feathers more than two inches long, very thickly set, and with hairy plumes curving over at the end. These can be laid back so as to be hardly visible, or can be erected and spread out on every side, forming a dome completely covering the head, and even reaching beyond the point of the beak; the individual feathers then stand out something like the down-bearing seeds of the dandelion. Besides this, there is another ornamental appendage on the breast, formed by a fleshy tubercle, as thick as a quill and an inch and a-half long, which hangs down from the neck, and is thickly covered with glossy feathers, forming a large pendent plume or tassel. This, also, the bird can either press to its breast, so as to be scarcely visible, or can swell out so as almost to conceal the forepart of its body. [13] "Athenæum," No. 1467. OWLS. These nocturnal birds of prey have large heads and great projecting eyes, directing forwards, and surrounded with a circle of loose and delicate feathers, more or less developed, according to the nocturnal or comparatively diurnal habits of the species. The position of the eyes, giving a particular fulness and breadth to the head, has gained for the Owl the intellectual character so universally awarded to it. The concave facial disc of feathers with which they are surrounded materially aids vision by concentrating the rays of light to an intensity better suited to the opacity of the medium in which power is required to be exercised. "They may be compared," says Mr. Yarrell, "to a person near-sighted, who sees objects with superior magnitude and brilliancy when within the prescribed limits of his natural powers of vision, from the increased angle these objects subtend." Their beaks are completely curved, or raptorial; they have the power of turning the outer toe either backwards or forwards; they fly weakly, and near the ground; but, from their soft plumage, stealthily, stretching out their hind legs that they may balance their large and heavy heads. Their sense of hearing is very acute: they not only look, but listen for prey. The Owl is a bird of mystery and gloom, and a special favourite with plaintive poets. We find him with Ariel:-- "There I couch when Owls do cry." He figures in the nursery rhyme of "Cock Robin." In reply to "Who dug his grave?"-- "I, says the Owl, with my little shovel-- I dug his grave." He hoots over graves, and his dismal note adds to the terror of darkness:-- "'Tis the middle of night by the castle clock, And the Owls have awakened the crowing cock; Tu-whit! tu-whoo! And hark again the crowing cock, How drowsily it crew. . . . . . . . . .