OF OUTHOPTERA IX THE CAUCASUS ANB WESTERN ASIA. 471 



climate of South Russia was colder and damper, which might 

 occur during the Glacial period. As a good many of the boreal 

 species, as for examijle. Mecosteihiis, J^soj^hus, Podisma ■pedestris, 

 are doubtless absent from Asia Minor, the latter supposition 

 should be by far the more correct. 



The remaining 22 Orthoptera of this district show rather 

 mixed affinities. The most marked affinity is that to the 

 Balkano- Anatolian f;iuna as expressed by the presence of Noca- 

 rodes ei/anipes, four species of Foecilimon, four Jsophya and two 

 Psorodonotus, while the direct influence of the steppe fauna is 

 evidenced by the presence of such forms as Stenohothrus macro- 

 cerus, St. parallelus, and Celes vai'iabilis variabilis. 



The endemic forms of the Western Caucasus are only four in 

 number: Podisma satunini^ P. riijipes, Isophya caucasica, and 

 /. kalischevskyi, their small number being a rather charactei'istic 

 feature of this fauna. 



The northern and southern boundaries of this district coincide 

 with the upper limits of the forests on the corresponding slopes 

 of the Caucasian chain ; while the eastern boundary, delimitating 

 Western Caucasus from the district of Eastern Caucasus, is as 

 yet insufficiently known ; I suppose it is somewhere near the 

 sources of the Terek and the Aragva. 



15. JJie district of Eastern Caucasus (C.Or.). 



Only 17 species of Orthoptera (11A + 5L + 1G) are known in 

 the eastern part of the Caucasian chain ; its fauna being thus 

 far poorer in comparison with that of the preceding district. 

 The most interesting features of this fauna are : the small 

 number of boreal and, in general, northern species and, further- 

 more, the presence of two exceedingly well characterized and, 

 therefore, very ancient endemics — Podisma lezgina and Pldocerus 

 onen.etriesi, the latter being the single representative of its genus. 



The boundaries of this district are easy to understand. 



16. TJie district of the Caiicastis Minor (CM.). 



The Orthopteran fauna of this district, being rather well 

 investigated, includes but 52 species (30 A + 18 L + 4 G), which 

 indicates its poverty. 



The analysis of this fauna indicates its close affinity to that of 

 Armenia, only twelve species being strange to the latter district, 

 as follows : — 



*Chrysochvaoii dispar. Pfficilimon similis. 



Stenobothvus werneri svirideiitoi. *Meconema tlialassinuni. 



Gomphocerus variegatus. *Plat3'cleis bicolor. 



*Avcj'ptera jflavicosta transcaucasica. * ,, weseli. 

 *PsopIius stridulus. ,, iljinskii. 



*Celes variabilis cavbonaria. *Decticus verrucivorus vcvrucivorus. 



The bulk of this group evidently belongs to species of boreal 

 origin (marked in the list with an asterisk), some of them being 



