IN EXTRA-TROPICAL COUNTRIES. 285 



Rhapis flabelliformis, Linn6 fil. 



China and Japan. This exceedingly slender Palm attains only a 

 height of a few feet. The stems can be used for various small 

 implements. It is one of the best plants for table decorations. It 

 bears the climate of the South of France to 43 32' K Lat. (Naudin). 



Rhaponticum acaule, Candolle. (Centaura Cynara, F. v. M.) 



On the Mediterranean Sea. A perennial herb. The root is edible. 



Rheum australe, D. Don.* (R. Emodi, Wall; R. Webbianum, Royle.) 

 Himalayan regions up to 16,000 feet. From this species at least a 

 portion of the medicinal Rhubarb is obtained ; most likely several 

 species furnish Rhubarb-root, and its quality depends probably much 

 on the climatic region and the geological formation in which the 

 plant grows. Should we wish to cultivate any species here for 

 superior medicinal roots, then clearly localities in our higher and 

 drier Alpine tracts should be chosen for the purpose. Hayne regards 

 the presence of much yellowish pigment in the seed-shell as in- 

 dicating a good medicinal Rhubarb-plant. As much as five Ibs. of 

 the dried drug are obtained from a single plant several years old. 

 An important orange-red crystalline substance, emodin, allied to 

 chrysophanic acid, occurs in genuine Rhubarb. A large proportion 

 of the medicinal Rhubarb-root is now grown in England. 



Rheum officinale, Ballion.* 



Western China and Eastern Thibet on the high table-land. Height 

 of stem 10 feet, circumference of foliage 30 feet, blade of leaf 2 feet 

 long and broad (Balfour). It furnishes most of the true Turkey 

 Rhubarb, not merely from the root but also from the woody stem. 

 Suited for mountainous regions. Recommended also as a scenic 

 plant by Regel. 



Rheum palmatum, Linne.* 



From insular to Alpine North-Eastern Asia. Attains a height of 

 9 feet. A variety from the Tangut country of Mongolia or North 

 Thibet, found by Col. Prejevalski, yields an excellent medicinal 

 root known as the Kiakhta or Khansu Rhubarb (Maximowicz) ; 

 indeed this is the best Russian Rhubarb ; valuable also as a 

 decorative plant. For medicinal culture alpine valleys with soil 

 rich in lime are needed. Sir Rob. Christison. 



Rheum Rhaponticum, Linne. 



From the Volga to Central Asia. This species, together with R. 

 Tataricum (L. fil.), R. undalatum (L.), and a few others, all Asiatic 

 (one extending to Japan), provide their acidulous leaf-stalks and 

 unexpanded flower-mass for culinary purposes. Rhubarb-leaves 

 can also be used in the manner of Spinage. 



