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BOTANY 



PART II 



Xerophytic plants of hot countries. Mesembryanlhemum ; a large genus, 

 especially in Africa. 



Family 4. Cactaceae. For the most part leafless plants with succulent stems, 

 natives of America. In size they range from very small to gigantic forms. Flowers 



FIG. 62S.Agrostemma Gitltago. Flowering shoot and fruit ( nat. size). Pomoxoi'S. 



hermaphrodite, actinomorphic, less commonly dorsiventral. Perianth of many 

 members, spirally arranged and showing a gradual transition from the calyx to the 

 corolla. Stamens and carpels numerous. Ovary inferior, unilocular, with numerous 

 parietal placentas. Ovules with long stalks. Fruit, a berry, the succulent tissue 

 being largely derived from the stalks of the seeds. 



Peireskia and some species of Opuntia possess leaves. Other species of Opuntia 



