257 



larger branches. Internal to this network of finer veins there 

 is a translucent aqueous tissue. The structure of the leaf 

 thus resembles that of Halostachys caspica (see above p. 201). 



Some of the herbaceous plants described under C, D 

 and E, are Halophytes e. g. Halopcplis, Suaeda, Halimocnemis, 

 Salsola, Halocharis, Anabasis, Statice and Zygophyllum. With 

 the exception of the two last-named they are Chenopodiaceae 

 and have thick assimilating organs of the centric type, which 

 is also the case with the vicarious branches of Statice. Linked 

 with Zygophyllum we have Euphorbia Turzaninowii, both 

 being thick-leaved and isolateral. Other representatives of 

 the Chenopodiaceae are xerophytic plants (Cornulaca, Horan- 

 inovia, Agriophyllum, Ceratocarpus). They are spiny, with 

 the assimilating organs thin and not succulent, but in the 

 two first-named the same centric structure is observed, 

 although on the whole they are better provided with scler- 

 enchyma; to the same category belongs Dodartia. Heliotrop- 

 ium and Cousinia are more nearly related to the hemicrypt- 

 ophytes with a more pronounced mesophytic structure (see 

 p. 237) since they have flat leaves not much modified. Such 

 leaves are as a rule isolateral, but dorsiventral also occur 

 (Frankenia, Euphorbia, Crozophora). 



The fruits exhibit a variety of types. 



The material of herbaceous plants available is however 

 insufficient to furnish a reliable general summary of the 

 conditions of structure. The foregoing must therefore be 

 regarded as a series of examples illustrating the different 

 modes of adaptation to the conditions of life in Transcaspia. 



If we endeavour, in conclusion, to summarise the features 

 of all the plants described in this chapter, - - keeping, how- 

 ever, in mente the Spring-plants it is possible to formulate 

 under three heads some of the specially characteristic features 

 of Transcaspian desert-plants. 



1. The difficulty attending the development of long- 

 lived aerial shoots. In this connection one must consider 



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