1893.] Geology and Paleontology. 267 
GEOLOGY AND PALEONTOLOGY. 
Geology of Eastern Siberia.—The Jnvestia of the East Siberian 
Geographical Society (Vol. xxiii, 3) contains an account of M. Obrut- 
cheff’s further researches in the Olekma and Vitim highlands. In 
the northeastern part of this region the author found a further contin- 
uation of the “ Patom plateau ”—that is, a swelling from 3500 to 4000 
ft. high, devoid of trees, with ridges and mountains rising over it to 
heights of from 5000 to 5600 feet. They consist of granite and crys- 
talline schists, probably of Laurentian age, covered with younger, 
probably Huronian, gneisses and schists. The other parts of the 
highlands consist of Cambrian and Ordovician deposits, while 
Silurian limestones and Devonian Red sandstones are met with in 
the Valley of the Lena. We thus have a further confirmation of 
the hypothesis, according to which the great plateau of northeastern 
Asia is a remnant of an old continent which has not been submerged 
since the Devonian epoch. Further traces of mighty glaciation have 
been found in the southeastern part of the region. As to the gold- 
bearing deposits, they are pre-glacial in the south and post- glacial in 
the north. The high terraces in the valleys are indicative of a con- 
siderable post-pliocene accumulation of alluvial deposits, and of a sub- 
sequent denudation on a large scale. (Nature, Jan. 12, 1893). 
Geological Features of Arabia Petræa and Palestine.— 
At a recent meeting of the London Geological Society, the following 
communication was read by Professor Edward Hull on the Geology of 
Arabia Petra and Palestine : 
The most ancient rocks (Archean) are found in the southern por- 
tion of the region ; they consist of gneissose and schistose masses and 
are penetrated by numerous intrusive igneous rocks. They are suc- 
ceeded by the Lower Carboniferous beds of the Sinaitic peninsula and 
Moabite tableland consisting of bluish limestone with fossils, which 
have their counterparts chiefly in the Carboniferous limestone of Bel- 
gium, and of a purple and reddish sandstone (called by the author 
“the Desert Sandstone,” to distinguish it from the Nubian Sandstone 
of Cretaceous age), lying below the limestone. The Nubian Sand- 
stone, separated from the Carboniferous by an enormous hiatus in the 
succession of the formations, is probably of Neocomian or Cenomanian 
age, and is succeeded by white and gray marls, and limestones with 
