Opening up land for cui.tiw-vtton 



1593 



(Meniocus Unijolius) . 

 Lepidium perfoliatum C. 



(Gypsophila muralis) C. 

 Echinc'Spermum strictum. 



X. Winter annuals. 



Echmospermtitn patulum. 

 (Filago aivensis) C. 

 (Trifolium arvense) C. 

 Delphinium Conaolida C. 



Camelina microcarpa. 

 Crepis tectorum. 

 Echinospcrmum Lappula. 

 Lithospermum arvense. 

 Sisymbrium Sinapistrum 

 (Sisytnbiium LoeseUi et 

 Sophia) C. 



Ceratocarpus arenarius. 

 Eebinnpsilon sedoides C. 



(Salsola tamariscina). 

 (Passerina annua). 



XI. Spring annuals. 



Eragrostis minor C. 

 Polygonum Bella rdi C. 



Atriplex pattila. 

 ^Xeranthemtim annuum). 



(Chenopodium album ?) 

 ( Poiycncmum arvense^ C 



XII. Parasitic phanerogams. 



Cuscuta planiflora. Orobanche coeru'lea. 



C — CRYPTOGAMS. 

 XIII. Mosses. 



Tortula ruialis. 



Grimmia. 



Parniella vagans. 

 Cetraria aculeata. 



( Urct'olaria scruposa) . 



XIV. Algae and lichens. 

 Nostoc commune. 



XV. Fungi. 



Probably the majority belong to the Angiocarpineae [Lycoperdon spp., Geaster spp.) 

 and Plectobasidineae {Pisolithus herculeum Fries). 



In the above table the species are divided into three phytosocial groups according to their 

 habitat. In the left hand column are placed those species which are more xerophytic than ty- 

 pical plants of the association and which are bordering on the next plant association i. e. sti- 

 pet'um cinereum. In an analogous way the species placed in the right hand column are all border- 

 ing on the more hydrophytic association /. e. stipetum latifolium. 



The names of the commonest species are printed in heavy type. Brackets mean th;it the 

 identification of the species is not very certain. Roman numerals are used to show that the 

 plant they follow occupies an inteirmediate position between the class in which it is placed and 

 the class indicated by the Roman figures. The letter C is used after the name of a species when 

 ever that species is a characteristic plant of the virgin steppe oi Ascagna Xova (Pontic re- 

 gion) which has been studied by J. K. Patzoskif. 



The dominant species all consist of perennial plants which occupy the soil in a more or 

 less stable condition, absorb more water and nutrient salts than any other species and are the 

 principal producers of organic matter. The secondary species on the other hand are all plants 

 which flower only once (annuals and bienniels). In the Ergenia stipetum s,ramineum the 

 dominant species are made up of 93 species or 61 per cent of the total number, while 

 secondary species, including parasite plants, are represented by 59 species only. 



