Page:Popular Science Monthly Volume 3.djvu/448

434 and perceived that the feathers corresponded with that named by Von Meyer. It seems to differ in only two particulars from ordinary birds: first, there are two fore-fingers, like hooks, projecting from the wings; and, secondly, the tail is shaped like that of the squirrel, with twenty vertebrae ranged in a line, each with a pair of quill-feathers attached. These variations are not sufficiently great to render it necessary to remove the Archeopteryx from the bird division, but they indicate in



what direction we are to expect a modification of the ornithic type, as it approaches the reptile. And it is in precisely these two respects that the Triassic Herpetoids differ from true birds.

The second link was furnished by the structure of the feet and the ichnites of the Iguanodon in England. Both pairs of limbs were terminated by three-toed feet, often of great size. Only two impressions appear, yet Prof. Owen supposes the tracks of the fore-feet were always covered by the hind-feet. The largest of these impressions are 28 inches long and 25 broad, and the stride sometimes reaches 46 inches. This was the largest of all the English terrestrial herbivorous reptiles, and his impressions have been extensively collected near Hastings.

The third link was furnished by the Hadrosaurus of New Jersey, the American representative of the Iguanodon. He appears to have had the general form of the kangaroo, enormous hind-limbs, terminated by trifid feet; a powerful tail, almost rudimentary anterior extremities, with a skull slightly ornithic, the height of the structure being from 12 to 15 feet. It is singularly like the Ichnozoa Gigantitherium. In fact, if we may follow the fashionable creed of the day, it may be said that the New-Jersey Hadrosaurus was the lineal descendant of the Massachusetts Gigantitherium.

For other links of this series it is only necessary to refer to the late publications of Cope, Huxley, Seely, Owen, Marsh, and other distinguished paleontologists, in which are described nearly a score of