107 



sella procumbens is a small, delicate annual plant which 

 disappears very quickly. 



The remainder of the plants of the spring-aspect in the 

 Sand-desert can be classed, like those of the Clay-desert under 

 the groups: Ephemerals, Hemicryptophytes and Geophytes. 

 The following species belong to the ephemeral s which are 

 the most abundant group: Triticnm squarrosum and desertorum, 

 Danthonia Forskalei, Schismus calycinus, Bromus tectorum, Bois- 

 siera bromoides, Avena sterilis, Hordeum murinum, Papaver 

 pavoninum, Hypecoum parviflorum, Capsella procumbens, Isatis 

 minima and emarginata, Tetracme quadricornis and recurvata, 

 Lachnoloma Lehmanni, Malcolmia circinnata, grandiflora and 

 Bungei, Streptoloma desertorum, Euclidium syriacum, Octoceras 

 Lehmannianum, Goldbachia laevigata, Chamaesphacos ilicifolium, 

 Lallemantia Royleana, Anchusa hispida, Nonnea picta, Echino- 

 spermiim semiglabrum, Plantago lachnantha, Statice spicata, 

 Valerianella Dufresnia, V. Szouitsiana, Crucianella filifolia, Ero- 

 dium bryoniae folium, E. oxyrrhynchum , Astragalus arpilobus, 

 Ceratocephalus falcatus, Delphinium persicum, D. camptocarpum, 

 Matricaria lamellata, Scorzonera glabra, S. hemilasia, Senecio 

 subdentatus , Koelpinia linearis, Lactuca undulata, Heteroderis 

 pusilla, Heteracia Szovitsii, Cousinia alata, tenella and minuta, 

 Dipterocoma pusilla, Centaurea moschata, pulchella and phyllo- 

 cephala, Silene nana, Psammogeton setifolium, Eremodaucus 

 Lehmanni, Aphanopleura capillifolia , Diarthron vesiculosum, 

 Atriplex dimorphostegium. 



Many species in this list occur also amongst the epheme- 

 ral plants of the Clay-desert. Those which I have not already 

 remarked on in the Clay-desert are of the same type: low, 

 mesophytic or slightly xerophytic plants, sappy and without 

 much mechanical tissue, and almost all with small leaves or 

 leaflets which are often more or less hairy. A few have gla- 

 brous leaves (Senecio, Diarthron). Thorns are found on Cou- 

 sinia alata and minuta, Centaurea phyllocephala, Centaurea 

 Moschata; a few others have rather broad leaves. Heteroderis 

 pusilla, Hypecoum and some Cruciferae have rosettes. 



A comparison between figure 17 and figures 5 and 6 

 will show that the ephemerals of the Sand-desert are of the 

 same type as those of the Clay-desert. 



