TCHIHATCHEFF ON THE ALTAI DISTRICT. 555 



being only replaced by these minute representatives. The only 

 apparent exceptions to this general condition are seen in the 

 animals of lowest organisation, such as the species of Calamopora 

 and Cyathophyllum. 



The examination of the fossil flora of the Altai (although at 

 present confined to the specimens brought by myself from the 

 carboniferous rocks) appears to conduct us to results of the same 

 kind as those arrived at by the investigation of its fossil fauna. 

 Among the numerous trunks of fossil trees and vegetable impres- 

 sions collected from the extensive carboniferous basin of Kouz- 

 netzk, we may trace a poverty of generic and specific types, 

 compared with the fossil flora of contemporaneous formations in 

 Europe and America, although the specimens examined almost all 

 belong to neAv species. Those that have been described again are 

 mostly referred to Coniferce, in so far therefore exhibiting a 

 tendency to approximate to the condition of existing creation, 

 and indicating a less tropical flora than that of other countries 

 during the same epoch. Whilst indeed the carboniferous rocks of 

 Europe and America contain a multitude of the remains of plants, 

 such as Lepidodeiidron, Sigillaria^ &c, whose nearest analogues 

 are to be sought at the equator, the same rocks in the Altai are 

 more especially characterised by species which, like Araucarites, 

 present the greatest analogy, if not a perfect identity with plants 

 which still form immense forests beyond the tropics, the Araucaria 

 not only abounding in New Holland, but attaining in Norfolk 

 Island gigantic dimensions, not inferior to those of the largest 

 specimens found in a fossil state. 



The Altai district therefore, whether considered with reference 

 to the direction of its mountain chains and other physical features, 

 or with regard to its fossils, appears to have little relation with 

 the geological formations of Europe and America. Differing, also, 

 not less from the mountain district of European Russia, the vast 

 expanse of Western Siberia is as it were isolated, and claims in its 

 geological description a separate consideration, destined perhaps 

 some day to be connected with investigations concerning the 

 geological constitution of northern and central Asia. 



D. T. A. 



