223 



The structure of the leaf is dorsiventral (fig. 51), but the 

 stomata and salt-secreting glands are found on both surfaces, 

 whereas the setaceous hairs are absent on the upper side. 

 There are long palisade cells on the upper side, generally 

 transversely divided, and short palisades on the lower side 



Fig. 51. Frankenia hirsuta. A, Outline of leaf in trans- 

 verse section with epidermis, palisade cells and hairs 

 indicated. B, Part of leaf in transverse section. Xy/., 

 Xylem; Phi, Phloem. C: Gland. A: X 47; B, C: X 203. 



and a loose spongy parenchyma with crystal-cells in the 

 middle. The air-spaces in the interior of the leaf are gener- 

 ally fairly large. Sclerenchyma is wanting. 



Convolvulus eremophilus Bois. & Buhse. 

 An undershrub growing on clay or stationary sand. The 

 year-shoots arising from the perennial branches are branched 



