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loma, Chartoloma and Octoceras; the Papilionaceae include 

 Ammodendron, Halimodendron, Ammothamnus, Eremosparton, 

 Alhagi and Astragalus. As representatives of otiier families 

 we may mention : Heliotropium, Echinospermum, Calligonum 

 (17 species) various Umbelliferae {Dorema, Ferula etc.), and 

 Compositae {Artemisia, Echinops, Cousinia, Microlonchus, Scor- 

 zonera, Streptorhamphus, etc.). The Salsolaceae are represented 

 by much the same species as in the salt-deserts, but they are 

 more luxuriantly developed; noteworthy are Alexandra Leh- 

 manni, Caroxylon (Salsola) hispidulum, C. subaphyllum, Eurotia 

 Eversmanniana. Smaller families are also represented by a 

 number of species: Zijgophyllaceae, Riitaceae, Tamaricaceae, 

 Gnetaceae (Ephedra), and of Monocotytedons the following may 

 be named: Biarum, Tulipa, Merendera, Gagea, Heleocharis. 



4) The area of the Serafshan River. 

 Lying as this does in the mountainous regions along 

 the upper courses of the river, it is outside of our area and 

 need not be considered. 



Following on the introductory description just summarised, 

 BoRSzczow then deals with the families of plants with respect 

 to the distribution of genera and species. This analysis oc- 

 cupies the greater part of his work and leads him to the 

 following general conclusions: 



"1. The majority of the commoner plants of Central 

 Russia with a distribution west of the Caspian Sea extending 

 to Trans-Caucasia, have as their southern limit of distri- 

 bution east of the Caspian Sea in Aralo-Caspia, the parallel 

 of 51 V2" N. lat. 



2. When these forms occur farther east in Siberia, the 

 boundary limiting their area of uninterrupted distribution 

 lies outside of Aralo-Caspia and always north of Sl'/a " 

 N. lat. 



3. Most of the typical steppe-plants met with in 

 southern Russia and distributed towards the west from the 

 Caspian to the foot of the Caucasus, attain their southern 

 limit in Aralo-Caspia at the parallel of 49 " N. lat., and 

 their eastern boundary at the meridian of the Mugodshar 



