CHAPTER VI 



SUCCULENT PLANTS 



THESE have thick, fleshy stems or leaves, or 

 both together, being true xerophytes, and grow- 

 ing in excessively dry situations or in maritime 

 districts and in saline marshes, in which the 

 salt has been experimentally proved to be the 

 cause of the succulency ; for although they may 

 be abundantly watered by sea-spray, as is the 

 samphire on rocks, while the marsh-samphire 

 actually grows in the saturated salt marshes, 

 they are called " physiologically " xerophytic, 

 inasmuch as the effect of the salt is to hinder 

 the absorption of water by the roots, the result 

 in structure being the same as if it were deficient, 

 as in the deserts. About Cairo, as it happens, 

 there is much chloride of sodium and magnesium 

 in the sand, which furnish a curious advantage 

 to certain plants. Thus the Tamarisk and 

 another plant of the same family, Reaumuria, 

 a little herb, excrete these salts, when water 

 is abundant in spring and is transpired, which 

 encrust the surface at the "water pores." In 

 the hottest time of the year, when dews are 



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