. The structure and life of birds. Birds; Evolution. SKELETONS OF BIRD AND REPTILE undergo, bones remain, relatively to each other, in the same position. Hence it often happens that to observe carefully the position of a bone is the best way to discover what bone it is. The wrist now follows, con- sisting of two rows of bones called Carpals (C, fig. 4a), with a central one (CE) wedged in between the two, after these the five Metacarpals, the bones of the hand (MC). Next to them come the finger bones, each division being called a Phalanx (D i, 2, 3, 4, 5). The thumb has two phalanges, the secon
. The structure and life of birds. Birds; Evolution. SKELETONS OF BIRD AND REPTILE undergo, bones remain, relatively to each other, in the same position. Hence it often happens that to observe carefully the position of a bone is the best way to discover what bone it is. The wrist now follows, con- sisting of two rows of bones called Carpals (C, fig. 4a), with a central one (CE) wedged in between the two, after these the five Metacarpals, the bones of the hand (MC). Next to them come the finger bones, each division being called a Phalanx (D i, 2, 3, 4, 5). The thumb has two phalanges, the second digit three, the third four, the fourth five, and the fifth three. And at the end of each digit is a claw. Apart from its being featherless, nothing less suited for flying can be imagined. If we turn now to the bird we shall find that the Hu- merus (HU, fig. 2) has broad- ened, especially at the nearer end, and is covered with great protuberances, good evidence that powerful muscles spring from it and are attached to it. Till we come to the fingers, there will be a striking increase in the length of the various bones. A bird's wing would be an outrageously long leg for a lizard of equal weight and bulk. When the long radius and ulna are ex- tended, the elbow-joint allows of no turning motion. As is essential for flight, they are held stiff whatever. Fig. 3 Tibia and Fibula of Fowl. F, fibula ; T, Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Headley, F. W. (Frederick Webb), 1856-1919. London, New York, Macmillan
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbirds, bookyear1895
