. The bird, its form and function . Fig. 50.—American Egret, showing curves into which the neck naturally fallswhen the bird is at rest. When striking at a fish the vertebras straightenout. very different. Watch a heron or, better still, a fla-mingo and see its neck describe figures of eight as hearranges the feathers on its back. Few people wouldever imagine that there are exactly twice as many neck-bones in a sparrow as in a giraffe, but such is the case,there being fourteen in the former and seven in the the neck of a swan there are twenty-three of thesebones. 74 The Bird The rema
. The bird, its form and function . Fig. 50.—American Egret, showing curves into which the neck naturally fallswhen the bird is at rest. When striking at a fish the vertebras straightenout. very different. Watch a heron or, better still, a fla-mingo and see its neck describe figures of eight as hearranges the feathers on its back. Few people wouldever imagine that there are exactly twice as many neck-bones in a sparrow as in a giraffe, but such is the case,there being fourteen in the former and seven in the the neck of a swan there are twenty-three of thesebones. 74 The Bird The remaining vertebra?, those of the upper and lowerback, ave very different from those of the neck. Theflexible neck enables the bird to reach all parts of itsplumage with its beak, and to pick up food from theground or from twigs overhead, but the all-importantfunction of flight must be provided for by means of a. Fig. 51.—White-throated Sparrow, three inches tall, with fourteen neck vertebrae.(Compare with Fig. 52.) rigid body-frame. In reptiles and in the embryos ofbirds only two pelvic vertebrae are fused together, butin adult birds many dorsal and caudal vertebra? (as manyas 23 in some cases) are fused into a single bone. Thusthe rib-bearing upper back vertebra? are partially fusedtogether, and below them those of the lower back havemerged until it is difficult to realize that this portion of The Framework of the Bird 75 the skeleton was not originally one bone. Passing on fora moment to the bones of the tail, we find a number ofseparate pieces, ending in a curious-shaped bone, calledthe ploughshare. This is at the tip of the tail, or popes
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectbirds, bookyear1906
