XCll PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



what less thick than was at first supposed ; while, on the other 

 hand, the Upper Silurian formation is considerably thicker than was 

 before stated. The author gives the following table as the general 



result: — 



Feet. 

 Oslo group and Oscarskal group 1100"! Lower Llandeilo and 

 Bed No. 9 . . . . 370 J Silurian. Caradoc. 



Malma group (without No. 9) . _460 { ^^^ Ztt'llZt 



1930 



The author then describes the metamorphic gneiss of Bugten and 

 Akershus, and particularly the geological features on the promontory 

 of Bugten, where the beds which by their fossils have been identified 

 with No. 9 dip partly under the gneiss and partly overlie it ; and 

 the result to which M. Kjerulf here comes is, that the gneiss partly 

 overlies the Lower Malmo schists, and that the lower divisions are 

 altogether wanting: '*we must therefore assume," adds the author, 

 '* that both a portion of the Lower Malmo schist, as well as probably 

 the whole of the older Silurian formations which are here wanting, 

 have been altered by metamorphic action into gneiss." M. Kjerulf 

 promises to send, by another opportunity, lists of the fossils of each 

 of the difi*erent subdivisions. The communication is accompanied 

 by a series of admirable sections, prepared by M. Kjerulf, to explain 

 the relative positions and geographical extent of the different groups 

 referred to by him. 



Russia. — A letter from M. Abich, published in a recent number 

 of the 'Bulletin de la Soc. Geol. de France*,' contains some in- 

 teresting details of Russian geology. He mentions that the recent 

 explorations of the ofiicers of the Corps des Mines, who have examined 

 the regions south of the Ural, and in the neighbourhood of the Sea 

 of Aral, show that an extensive eocene deposit, with a molluscous 

 fauna rich both in genera and species, occurs on the eastern and 

 southern shores of that lake. They are mostly identical with those of 

 the Paris basin, and in an admirable state of preservation. These 

 eocene beds overlie nummulitic limestones, resembling those in the 

 Mediterranean basin, and beneath them is the chalk. The inferior 

 cretaceous and Jurassic formations crop out on the steep banks of the 

 Aral. The gault and neocomian beds contain the same fossils as to 

 the north of the Caucasus. The eocene formations of these Aralo- 

 Caspian regions are again covered by the middle tertiary formation, 

 which forms the upper portion of the Ust Urt, the absolute elevation 

 of which is greater than the maximum of the mean level of the more 

 recent deposits called Aralo-Caspian in the whole space of the Aralo- 

 Caspian table-land. The soil of the whole of this region belongs to the 

 middle tertiary formation, and is characterized by the same fossils as 

 occur in Volhynia, Podolia, and Bessarabia. The existence of this vast 

 eocene basin, which extends far beyond the sea of Aral, will greatly 

 add to our data for the knowledge of the geological structure of the 



* Vol. xii. p. 115. 



ii 



