Physiographic processes, by J.W. Powell.--Physiographic features, by J.W. Powell.--Physiographic regions of the United States, by J.W. Powell.--Present and extinct lakes of Nevada, by I.C. Russell.--Beaches and tidal marshes of the Atlantic coast, by N.S. Shaler.--The Northern Appalachians, by B. Willis.--Niagara Falls and their history, by G.K. Gilbert.--Mount Shasta, a typical volcano, by J.S. Diller.--The physical geography of southern New England, by W.M. Davis.--The southern Appalachians, by C.W. Hayes.

The purpose of this work is to provide those contemplating scientific or engineering activities in cold regions with a general picture of their geology and physiography. The cold regions are the Arctic, Alaska, Canadian Arctic and subarctic, Greenland, Iceland, Jan Mayen Svalbard, Scandinavia, U.S.S.R., and the Antarctica.

White pine blister rust is widespread and abundant on sugar pine in northwest California. In the central Sierra Nevada, it tends to occur in "pockets" in canyons and stream basins. Records of infection near the southerly limit of the disease were scrutinized. Data from 14 areas were studied statistically. Eight physiographic factors were computed for each rust center. Canyon physiography and intensity of rust were markedly correlated. A records approach to prediction of future rust incidence in the central Sierra Nevada could be useful in planning control work.