SUCCULENT PLANTS. 



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foliaceous tubercles, smooth or fissured above. The plants are all most 

 curious. A. fissuratus is most frequently cultivated, and the tubercles on 

 the upper surface are remarkably fissured ; it has rose-coloured flowers. 

 The following key of the genera Ariocarpus and Lophophora is abridged 

 from the valuable account by Mr. C. H. Thompson in the Ninth Eeport 

 of the Missouri Botanical Garden : 



I. Tubercles evident, triangular, epidermis cartilaginous. Ariocarpus. 



Tubercles with wool-bearing groove. 



Tubercles fissured above. A. fissuratus. 



Tubercles flat and finely papillose. A. Kotschubcyanus. 

 Tubercles not grooved above. 



Tubercles reflexed and closely imbricated. A. furfurascens. 



Tubercles more open, squarrosely spreading. A. retusus (" Bot. Mag.,' 

 t. 7279). 



II. Tubercles scarcely evident, epidermis flexible. Lophophora. 



Ribs, commonly 8, quite regular. L. Williamsii. 



Ribs, commonly 13, irregular to much broken. L. Leivinii. 



A. fissuratus has been given the popular name "Living Rock." The 

 species are natives of Mexico. 



Lophophora. — This generic name has not, I believe, been used in 

 gardens, but it usefully separates two plants that are very distinct from 

 any with which they have been associated. [See above.] L. Lewinii may 

 prove, I believe, to be only a variety of L. Williamsii. They have no 

 spines, and, when quite healthy, the flesh is remarkably yielding to the 

 touch and grey in colour. L. Lewinii (and no doubt L. Williamsii is 

 quite of the same character) produces a very poisonous fruit which, being 

 dried, is known as Muscale Buttons, and is chewed by the Mexicans and 

 Indians. The result is a feeling of ideal content, the mind remains 

 self-possessed, but there is an intoxicating orgy of glorious visions in 

 which are seen the most marvellous colour effects. An interesting 

 account is given under the heading of "Drug Dreams" in the January 

 number of the " Grand Magazine," 1907. Paragraphs on the drug will be 

 found in the "Pharmaceutical Journal." The popular name "Whiskey 

 Plant " has been used. 



Pclecyphora. — A very curious and distinct genus. The stem is 

 club-shaped and covered with short tubercles, each terminated by a 

 scale in the place of spines. There are two species, P. aselliformis 

 with flowers tending to carmine but variable in shade, and P. pcctinata 

 with yellowish flowers. Both are natives of Mexico. 



Lcuchtcnbergia. — This is one of the most remarkable of the genera of 

 Cactaceae. There is only one species, L. principis (fig. 75). In developed 

 plants the base of the stem is naked, above are the much-elongated, 

 three-sided tubercles, three to six inches long, and at the apex are several 

 long, flat, awn-like structures. Years ago it was thought that the flowers 

 must be produced as in Mamillaria, but now it is well known that the 

 flowers are produced at the apices of the younger tubercles — usually 



by Hennings. These plants by Coulter (Contr. U.S. Nat. Herb. 3. 131) are established 

 to form the genus Lophophora, and as such it should, I think, be maintained. They 

 are quite unlike all other Cactaceae, and a separate genus for them is therefore 

 probably correct. 



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