Page:Popular Science Monthly Volume 86.djvu/265

Rh present environment in the southern portion of the Great Valley of California.

The fragmentary remains obtained by Mr. Buwalda from the deposits of Manix Lake include only scattered bones and teeth with a few shells of snails and clams. The collection includes the bones of two horses of the genus Equus. One is a large species evidently closely related to the existing horses. The other is a much smaller form, but evidently of the same genus. There are two camels; one near the size of the dromedary, the other much smaller. The larger camel was probably near or incidental with the large Camelops known by splendid specimens from Rancho La Brea. The other species is unlike any Pleistocene camel described from the west. There are bones of a proboscidean, probably an elephant. A large antelope, probably like the pronghorn is known by a single bone. Two birds like existing species are found in this fauna. The molluscs are fresh-water species closely related to living forms.

As fragmentary as is the material from the beds of Manix Lake, it represents the first assemblage of mammalian species of Pleistocene age from a definitely known horizon in the Mohave region. It is, in fact, the most important collection made at any single locality in the Pleistocene of the Great Basin. It gives for the first time a grouping of the most important mammalian forms living together in this region at any particular stage in the Pleistocene.

Taken alone these fragmentary specimens might never tell more than a very short story, but the wonderful Pleistocene collection obtained at Rancho La Brea just across the range to the west will ultimately furnish comparative material adequate to make possible a definite determination of the animal represented by every bone found in the Manix beds.

The Manix fauna is entirely distinct from that of the Ricardo. The horses are of the latest and most advanced genus, that is the modern Equus, which includes most of the living representatives of the horse group. The larger camels seem to represent the last genus known in North America. The relationships of the smaller camel are as yet uncertain. If the antelope is near the pronghorn, as seems probable, it is also of the latest known type.

It is perhaps unnecessary to state that the Manix fauna differs from that of the present day in the inclusion of camels and a proboscidean. When it is better known, this fauna will probably be found to contain few if any modern species.