Kansas fossils the fact was established that birds with teeth formerly existed.
The deposits of Kansas in which the Hesperornis has been found have yielded also the remains of another Cretaceous bird,
Fig. 4.—Restoration of Ichthyornis victor (after Marsh). One half natural size.
the Ichthyornis. This animal was small, of about the size of the tern, and probably also resembled it in its habits and mode of aliving; at any rate, it was a good flier, with powerful wings and small legs. The Ichthyornis also had teeth in both jaws. But in still another respect it was different from all our present birds. The articular faces of its vertebræ were not saddle-shaped, but simply excavated on both sides; they were biconcave. This form of vertebrae is met with in a few recent and many extinct reptiles, and in the amphibians. But it is especially characteristic of fishes, and the name has been chosen on account of it, for Ichthy-
