OF ORTHOPTERA IN THE CAUCASUS AND WESTERN ASIA. 455 



after the end of the Ice age, southwaids into the monnta.ins of 

 the Caucasus (see p. 448). Of the remaining six species, four 

 are of Mediterranean (resp. Balkano-Anatolian) origin ; these 

 are : Pcecilimon similis, Paradrymadusa heckeri (peculiar to the 

 Kuban-Terek district, but belonging to a Balkano-Anatolian 

 genus), Flatycleis fusca, and Ilyrtnecojihila ochracea, which ai'e to 

 be regarded as immigrants from Transcaucasia.. The ways of this 

 migration, doubtless, do not lead across the chain of the Great 

 Caucasus, but I think they go on the west along the shores of 

 the Black Sea, and on the east through the Somkheto-Ivakhetian 

 and Daghestan districts (see below). The remaining two species 

 are : fii'stly, Gampsocleis schelkovnikovce, which has just been 

 described and the zoogeographieal physiognomy of which is as 

 yet uncertain ; secondly, Nemohius tartarus, which has recently 

 penetrated into the Kuban-Terek district from the neighbouring 

 deserts of the Caspian Ciscaucasia. 



Thus the Orthopteran fauna of the Kuban-Terek district 

 may be characterised as derived from the South -Russian Steppe 

 fauna, with well-marked indications of southern influences — from 

 Caucasus (forms of boreal origin) and from Anatolia (Balkano- 

 Anatolian species). 



The Kuban-Terek district comprises all the northein slopes 

 of the Caucasian mountains, including the adjacent hilly country 

 with insular forests ; its northern boundary coincides with the 

 northern limit of these forests on the west and of the grass steppe 

 on the east ; while the southern is formed by the upper limit 

 of the forests on the main chain of the Caucasus. 



3. The Daghestan district (D.). 



The fauna of this interesting district has as yet been very little 

 investigated : the whole number of species known from it is 

 only 43 (2 M -}- 23 A -f 12 L -f 6 G), which is, certainly, not 

 more than one third of the real number. Notwithstanding, 

 a careful analj'sis of this fauna allows us to draw some veiy 

 interesting conclusions as to its composition and origin. 



The Daghestanian Orthopteran fauna is in direct contact with 

 the faunas of four districts: Kuban-Terek, Somkheto-Kakhetian, 

 Caspian Transcaucasia, and the Eastern Caucasus. But we find 

 the closest resemblances between our fauna in the two first named 

 districts, and as they belong to distinct subregions (Steppe and 

 Mediterranean respectively), it is an interesting problem to be 

 solved — in which of them the Daghestan should be included. 



Out of 39 Daghestanian Orthoptera 34 are common to 

 Daghestan and to the Kuban-Terek distract, and only five are 

 distinct, as follows : Nocarodes sen-icollis, Orj^hania scutata 

 zacharovi, Locusta caudata caudata, Decticus verrucivorios 

 verrucivorus, and Platycleis daghestanica. The last named species 

 is peculiar to the Daghestan and of no interest to us ; Nocarodes 

 serricollis is not to be considered as being characteristic of 



