. The bird, its form and function . n the slightest breeze andgives him a rather untidy appearance, the cock is an ex-ceedingly handsome bird. So we have here an isolatedcase of direct relation between two organs, the balanceof power changing from wing to feet and affecting muchof the birds structure, even the plumage losing its cohe-siveness. The weak-flying Tinamou have unusually sturdylegs, and many other instances might be mentioned. For many reasons the most interesting of all birdsfeet are those of the ostriches and their allies, and amongthem the most extreme examples of this same cause
. The bird, its form and function . n the slightest breeze andgives him a rather untidy appearance, the cock is an ex-ceedingly handsome bird. So we have here an isolatedcase of direct relation between two organs, the balanceof power changing from wing to feet and affecting muchof the birds structure, even the plumage losing its cohe-siveness. The weak-flying Tinamou have unusually sturdylegs, and many other instances might be mentioned. For many reasons the most interesting of all birdsfeet are those of the ostriches and their allies, and amongthem the most extreme examples of this same cause andeffect are to be found. 394 The Bird When one trains in college for a long-distance race,one rule to observe is, never touch your heels to the ground;run wholly on the ball of the foot. Untold centuriesago, wise old Nature whispered the very same directionto those of her children who had most need to run fortheir lives in lifes great race, and down through theages some of them have never broken training. When an animal acquires. great speed in runningor leaping, there is atendency for one toeto become greatly en-larged at the expenseof the others, as isseen in the case of thehorse, the kangaroo,and the ostrich. In the horse onlythe middle toe isfunctional, the secondand fourth having de-generated into thesmall splint-bones atthe side of the leg. The kangaroo progresses uponthe fourth and fifth toes, the second and third beingsmall and skin-bound. The ostrich has but two toes,one of which, the third, as in the case of the horse, isvery large and armed with a thick claw, which, hoof-like, grows close to the toe. This toe supports most ofthe birds weight, while the fourth or outer toe is only Fig. 308.—Feet and legs of Cassowary. Feet and Legs 395
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectbirds, bookyear1906
