GEOLOGY. The geology of the Arctic lands presents a great variety of features, which, how ever, are comparable in general to those exhibited in more southern latitudes. Extensive coal beds and numerous fossil remains in sedimentary strata bear evidence that the conditions prevail ing in former ages were favorable for the de velopment of a diversified fauna and flora, such as do not at present exist. The Carboniferous strata are the most significant as to the past cli matic conditions obtaining in this region. They have been found in Banks Land, North Devon, and Spitzbergen. Coal beds and strata of the Tertiary Age have been discovered in Grinnell Land, and similar deposits are known to occur as far north as 82°. in which poplar, pine, birch, and hazel flora are represented. In Spitzbergen Carboniferous flora has been obtained, comprising no less than twenty-six species. some of which
are new, but of which others are forms common to the coal measures of England and the United States. Greenland (q.v.) consists principally of gneisses, schists, and granite, with later in trusions of basalt, and is noteworthy as the source of the mineral, cryolite. Most of the islands off the North American Continent are made up of crystalline rocks and Paleozoic sedi ments, of probably Cambrian and Silurian Age. The northern part of Seward Peninsula has been found recently to be composed of metamorphosed sediments of undetermined age, and of Cretace ous limestones. The great island groups north of Euro-Asia, including Franz-Josef Land, are formed of early Paleozoic and pre-Cambrian rocks overlaid by basalt. Very little is known as to the geological features of northern Siberia.