Xeromorphy 



The structure or form characteristic of organs of Xero- 

 phytes (q. v.), e.g., tough, leathery leaves on some desert 

 shrubs. 



Xerophilous, Xerophytic 



Refers to a plant that is capable of growing in dry places, 

 e.g., cactus, cf. Xerophyte, Hydrophilous, Mesophyte. 



Xerophyte 



A plant that can grow in dry places, e.g., creosote bush, 

 cactus, cf. Xerophilous. 



Xeroplastic 



Refers to characteristics which are developed under the 

 influence of drought. 



Xerosere 



A series of successional stages beginning in a dry area, 

 cf. Hydrosere, Sere, Xerarch. 



Xerothermic 



Refers to a dry and warm climatic period, e.g., one of 

 the postglacial periods. 



X-rays 



Electromagnetic rays, 0.1 to 50 mu, shorter than Ultra- 

 violet and longer than Gamma rays. 



Xylem 



Woody tissue in the Stele (q. v.) of plants, conducts water 

 and substances in solution. 



Xylophagous 



Refers to organisms that consume wood. 



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