235 



Zygophyllum. 



The species of this genus are to some extent at least 

 summer-plants. Z. Eichwaldii C. A. M. may be taken as an 

 example. It has long furcate shoots sparsely covered with 

 leaves. These have long stalks and are pinnate with small 

 flat leaflets. The older leaves die off and fall while the apex 

 of the stem is still growing (Translocation of water, comp. 

 above p. 71). The plant flowers in spring (also in summer?), 

 but may still be found with living shoots well into summer. 





Fig. 60. Anabasis eriopoda. A, Part of stem in transverse section; Phi, 



phloem within which lies wood with vessels. B, Details of A ; C, Epidermal 



tissue with stoma. A, X 47; B & C, X 203. 



The leaf is isolateral and in contrast to the species des- 

 cribed by WARMING 1897 (p. 41) and VOLKENS (p. 113) it 

 consists of palisade cells throughout.. These become largei 

 and more translucent towards the interior, but they all con- 

 tain chloroplasts, hence there is no aqueous tissue present. 

 The epidermis consists of one layer and seems to be mucil- 

 aginous, the stomata are slightly sunk. 



