Editorial Miscellany. 185 



advanced state of art than was possessed by any of the modern Indian 

 tribes. 



The Second Division, under Mr. Powell, is still in the field, and the 

 full results of its labors can not be given. They include similar dis- 

 coveries in the valley of the Colorado, besides the collection of many 

 speoiniens of ancient picture-writing, implements, etc., and photo- 

 graphs of cave dwellings in the cliffs near the St. Elmo, and the ruins 

 of dwellings and fortified places elsewhere. 



Ancient Lake Basins. — Prof C. C. Marsh contributes to a recent 

 issue of the American Journul of Science and Arts the first part of an 

 interesting paper on "Ancient Lake Basins of tlT,e Rocky Mountain 

 Region." The geological explorers of the "bad lands" have estab- 

 lished the existence of several basins of tertiary fresh-water 'lakes, 

 which Prof. Marsh briefly discusses under the three divisions : Eo- 

 cene, Miocene and Pleiocene, corresponding Avith their relative age. 

 He states that the general characteristics of these basins indicate suc- 

 cessive elevations and depressions of the surface, which sometimes 

 brings into juxtaposition deposits of widely separated periods. Thus, 

 the Green River basin, lying between the Rocky Mountains and the 

 Wasatch Range contains deposits of great thickness, yielding 140 

 species of extinct Eocene vertebrates, Avhile, overlying the eroded 

 deposits, are strata composed of water-worn debris of the surrounding 

 mountains of a comparatively recent period. 



The fauna of the Eocene lakes indicates a tropical climate, and 

 includes a great number of animals of the tapir kind, monkeys, 

 crocodiles, lizards and serpents. The flora seems not yet satisfactorily 

 determined. 



The Miocene lake deposits contain the wonderful vertebrate fauna, 

 made known chiefly through the researches of Prof. Hay den, of the 

 recent military exploration. These basins indicate comparatively 

 shallow and quiet watei's. In these, also, there is evidence of the lake 

 bottom having for a long period been exposed as dry land to the 

 erosive action of rains, but subsequently submerged and reconverted 

 into a lake, which deposited extensive beds of clay and sand over the 

 same area. 



The fauna of the White river lake basin indicates a climate less trop- 

 ical than that of the Eocene lake, as seen in the al)sence of monkeys 

 and scarcity of reptilian life. The Brontotheridse, the largest known 

 Miocene mammals, are peculiar to the lower strata of this basin. 



The Pleiocene basins were formed by a subsidence east of the 

 Rocky Mountains at the close of the Miocene period, formmg an ex- 



