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MESEMBBIANTREMUM CALCABEUM, Marloth: 

 A NEW MIMICEY PLANT. 



By E. Marloth, Ph.D., M.A. 

 (Bead June 26, 1907.) 



In my former communications* to our Society I have shown that 

 there are a number of plants in the karroid districts of South Africa 

 which resemble the stones among which they grow to such an extent 

 that they are to be detected at their natural habitat only with 

 difficulty when not in flower. Although I was fully aware of the 

 scepticism with which mimicry among plants is treated by some 

 botanists, and although I am very sceptical myself about various 

 cases of so-called mimicry of plants, I could not help recognising 

 that several of these plants were so exactly like their surroundings, 

 in colour as well as in shape, that they would easily escape the 

 attention of animals, especially at night-time. 



After the publication of my observations several botanists have 

 discussed the same subject at home., e.g., Thiselton-Dyerf in "The 

 Annals of Botany," and Bechhold I in the " Umschau," but these 

 writers are under a great disadvantage, for all desert plants lose a 

 great deal of their physiognomical characters when cultivated in 

 a damper atmosphere and with a largely reduced supply of light. In 

 fact, one can often hardly recognise the species when cultivated at 

 home. 



In the meantime, a few more such cases have come under my 

 notice. These are three species of Mesembrianthemum, among them 

 two that are new to science. The third one is M. canum, Haw., a 

 plant that grows in the karroo, near Miller station, on the Oudts- 

 hoorn line, and which had been lost sight of for more than half 

 a century. 



Of the new species one was mentioned in my last paper on 



* Vol. XV., p. 97, and vol. xvi., p. 165. See also Dinter, in Garcl. Chron., 1900, 

 pp. 115, 211. 



t "Ann. Botany," vol. xx., p. 124. + " Umschau," 1906, p. 525. 



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