Page:Popular Science Monthly Volume 4.djvu/488

472 great lights—Prof. Joseph Leidy, Prof. E. D. Cope, and Prof. O. C. Marsh. The last two, with an enthusiasm that has triumphed over great difficulties, have especially produced startling results in their individual explorations of the great graveyards of the ancient dead in our Western Territories. Of the labors of Prof. Cope, as conducted under government auspices, it is proposed here to offer a few results. We shall simply give some details of his work done last summer, as the vertebrate paleontologist in behalf of Prof. F. V. Haydon's "Seventh Annual Report of the United States Geological Survey of the Territories." Prof. Cope found himself literally in a crowded cemetery of a quadrupedal race long extinct.

The list which now immediately follows is limited almost exclusively to the Miocene fossils of "the Bad Lands" of Colorado. It tells a marvelous story of rich and formidable fauna that existed on our virgin continent in that Middle-Tertiary age. The Rodents, or gnawing animals, were well represented. Five genera seem to be established, embracing eighteen species. The predecessors of the squirrels were there. One, named Paramys, was a little larger than our chickaree. One little creature, called Heliscomys, had four teat-like cusps on the crown of each molar in the lower jaw. This was the tiniest thing of them all, and stood, probably, among the Miocene rodents, as the common mouse does among the gnawers of to-day. If, indeed, Heliscomys be the ancestral mouse, our Mus musculus has a very ancient pedigree. The rabbits were represented by the genus Palæologus.

There are eleven species of Insectivora, arranged under five genera, with the names Domnina, Embasis, Miothen, Herpetotherium, and Isacis. Except the last one, all these are allied to the mole. They had doubtless the same burrowing habits and food appetencies as the Talpa tribe that to-day follows and annoys the gardener at his work. It is an item gained of real knowledge as respects animal habits, to learn that the earthworms and the subterranean larval insects were kept in check in the same manner then as now. And, if these are the predecessors of the Talpa race, we would like to know if the primitive stock were as clever engineers at constructing subterranean earthworks, for the mole to-day is a genius in that line. There are six species in the list, and they differ quite a good deal in size; and would seem also to differ in some more important aspects, as the name of the Herpetotherium signifies the "crawling beast." It is worthy of remark that these ancient moles, like the modern, were very small animals. Necessarily, then, the fossil bones must have been very minute. They are, however, preserved with wonderful perfection.

As to that other insect-eater, Isacis, it represented the existing hedgehog, as shown by its anatomical structure. And as snakes abounded then, probably, like its congeners now, it made many a meal of them, utterly regardless even of those poison fangs, if such they