. A history of birds . hat we now know as the wing was originally afive-fingered organ. We meet with it for the first time in theskeleton of the Jurassic ArchcEopieiyx, and here it has alreadyacquired its peculiar tridactyle form. The arm and forearmdiffer in no respect from the same bones in modern birds, norcan the carpus be said to offer any essential points of difference-But, assuming the fossil remains of the only two specimens ofArchcBopteryx so far discovered to be skeletons of adult birds,it is important to notice that this complex of wrist bonesremained free throughout life, while in
. A history of birds . hat we now know as the wing was originally afive-fingered organ. We meet with it for the first time in theskeleton of the Jurassic ArchcEopieiyx, and here it has alreadyacquired its peculiar tridactyle form. The arm and forearmdiffer in no respect from the same bones in modern birds, norcan the carpus be said to offer any essential points of difference-But, assuming the fossil remains of the only two specimens ofArchcBopteryx so far discovered to be skeletons of adult birds,it is important to notice that this complex of wrist bonesremained free throughout life, while in modern birds this indi-viduality is retained only for the first few weeks of life, as acomparison of the accompanying illustrations will show. So,too, with the bones of the middle hand or metacarpus, though 374 A HISTORY OF BIRDS to a much less extent. In these fossils indeed, fusion seenis tohave taken place, but not so completely as to obliterate the tell-tale sutures. The Answers differ from those of modern birds in. two particulars—each terminated in a large claw, and the thirdfinger had as many as four phalanges, or separate segments,as against a single phalanx in modern birds. Claws occur to-day only on the thumb and second finger, and here they are
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbirds, bookyear1910
