Page:Bird-lore Vol 08.djvu/76

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52 Bird -Lore forms of feathered life. The real foot of a bird, as the term is used in speaking of the foot of other animals, extends to the backward bending joint, or heel. Part of the lower leg is concealed by the feathers and skin, while the upper leg, or thigh, is generally wholly within the body. The Crow, in many respects standing near the top of the scale of bird-life, nevertheless has found it good to hold to the typical bird's foot. And indeed it serves him well, for with it he can walk on snow or ice, wade in shallow water, perch in trees, scratch or claw the ground, and hold down a crab shell while he extracts the edible portion. Not only this, but he can hop like a Sparrow or walk like a Chicken at will. No hard and fast rules can be laid down, but it is generally the case that birds which are especially at home in the trees usually hop with both feet simultaneously on the ground. Ground -nesters and feeders, such as the Meadowlark, Quail and Vesper Sparrow, walk or run. The great order of perching birds shows to what varied uses the typical foot can be put. All birds of this order have three toes in front and one behind, and there is scarcely a place on the globe to which these birds have not adapted themselves; and recently too, as would seem probable from the similarity of foot-type running through all. The majority of these birds are arboreal, and the strength of the tiny tendons which run down the leg and through each toe is sufficient to clasp and unclasp a thousand times a day, and to hold and balance the bird on whatever bending twigs or wind-blown foliage it chances to alight. The Creepers are, so to speak, passerine Woodpeckers, and forever wind their spiral paths about the tree-trunks. But the Nuthatch excels all other birds in his climbing ability. With no support whatever from the tail, and without marked adaptation of toes, it defies all laws of gravitation, and creeps up and down or around the vertical tree-trunks as if on level surface. Never a misstep, never a slip, but each foothold as secure as if its feet were vacuum- cupped. In the Swallows the feet are very small, having fallen into disuse with the great increase of the power of flight. Orioles and Weaver-birds make occa- sional use of their feet to hold a strand of grass or string, which they are weaving with their beaks into their elaborate nests, and certain Flycatchers pounce upon and hold their insect prey as an Owl grips a bird, or a Jay clings to a nut; but with the exception of a few such cases, the feet of perching birds serve principally the function of locomotion. Although the bill is an important organ among the perching birds in procuring food, yet such birds as the Chewink, the White-throated Sparrow and the Jays use their feet to scratch away dead leaves and rubbish in search of small insects. There are many curious things about a bird's toes, to which we have not yet found the key. Who can tell why the Horned Larks and some other