the eastern continent in late Cretaceous times will be discovered. [Illustration: FIG. 90.—Pectoral girdle of _Champsosaurus_. (After Brown.)] [Illustration: FIG. 91.—_Champsosaurus_; pelvic bones. (After Brown.)] The choristoderans began their existence, so far as is now known, in North America in late Cretaceous times and died out in both Europe and North America in early Tertiary times. That is, they were one of the few branches of reptilian life which not only witnessed the extinction of the great dinosaurs and plesiosaurs, but the advent also of the early placental mammals. They lived millions of years after the proganosaurs became extinct, and, similar as they are in form, there is no relation between them. Moreover, in all probability they did not migrate to the eastern continent over the same route. The structure of the head and teeth of the Choristodera clearly indicates a fish-eating habit, or at least a diet of soft-bodied, free swimming invertebrates. The legs and ribs, as also the armor of ventral ribs, like those of the plesiosaurs, point very insistently toward a bottom-crawling habit while in the water. CHAPTER XIV PARASUCHIA The first known specimen of the order of reptiles now generally known as the Parasuchia was found in Würtemberg, Germany, in 1826 and very briefly and inadequately described[4] two years later by Professor George Jaeger. The specimen was a sorry one, and was sadly misinterpreted by Jaeger. It consisted chiefly of casts of the alveoli or sockets of a number of teeth, more or less connected by corroded or decomposed portions of the jaws. He recognized the casts as teeth of a peculiar reptile, but mistook the roots for crowns, and, naturally concluding that such obtuse teeth would be of use only for the mastication of vegetable food—about the last kind of food to which the phytosaurs were addicted—called the animal _Phytosaurus_, meaning plant saurian. Because of differences he observed in the shapes of the teeth he thought that they belonged to two distinct species, which he called _cylindricodon_ and _cubicodon_; but the differences were due simply to the different positions they held in the jaws. [4] “The author showed drawings and some specimens of two hitherto unknown reptiles from the white, coarse-grained sandstone, of which one in the form of the skull resembles the gavial, but is distinguished by the cylindrical form of the lateral teeth of the jaws; he therefore calls it provisionally _cylindricodon_, and a second species or genus, of which, however, so far only fragments of the jaws have been found, because of the four-cornered form of the teeth, _cubicodon_, while at the same time for the genus or family, to which the remains of these animals have belonged, he proposes the name _Phytosaurus_, since the teeth seem to be more adapted to a vegetable diet, even though they have not been worn away, as in _Iguanodon_.”—_Isis_ (1828), p. 441 (translation).