. The bird, its form and function. Birds. The Framework of the Bird 89 way to locate these is first to find the socket in which fits the head of the thigh-bone. This is the deep ciij)- shaped depression on each side, and all three bones join in making the socket. The ilium lies along the back and forms a sort of roof over the portion of the back- bone in this region. If we look at the under side of this bone, we may see the fused vertebrse more distinctly— fourteen or fifteen of them. The two deep depressions in which the kidnej's of the bird were located are also. Fig. 62.—Pelvic girdle of a
. The bird, its form and function. Birds. The Framework of the Bird 89 way to locate these is first to find the socket in which fits the head of the thigh-bone. This is the deep ciij)- shaped depression on each side, and all three bones join in making the socket. The ilium lies along the back and forms a sort of roof over the portion of the back- bone in this region. If we look at the under side of this bone, we may see the fused vertebrse more distinctly— fourteen or fifteen of them. The two deep depressions in which the kidnej's of the bird were located are also. Fig. 62.—Pelvic girdle of a bird. now visible. As the coracoid is the great pivot of the wing, so the ilium helps most to bear the strain of hop- ping and running. In the frog, which progresses by hops or great leaps, the ilium is also largely developed; indeed we can see it through the skin, thus giving the broken-back appearance to that creature. Each side of the thigh-bone box is formed by the ischium, which is closely fused with the ilium except in most of the ostrich-like birds, the tinamous, and in reptiles, where these bones are free throughout their entire length. We can readily make out the pubis as a slender bar of. 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 Beebe, William, 1877-1962. New York, Holt
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectbirds, bookyear1906
