107 



RHEUM OFFICINALE, continued. 



Russian rhubarb, but receives its name from the country from which it 

 is imported. For description of the plant yielding it, see P. J. [8] , 

 vol. Hi., p. 301 ; vol. iv., p. 690. Some of the East Indian rhubarb of 

 commerce is also derived from Rheum palmatum, var. Tanguticnm, Max. 

 See P. J. [8], vol. v., p. 784. EegeVt Garten Flora, Jan., 1876. For 

 collection of the root, see P. J. [1] , vol. ii., p. 658 ; [2] , vol. vii., p. 875 ; 

 Pharmacographia, p. 442. East Indian rhubarb is distinguished by the 

 small size, dark colour, and irregular shape of the holes with which it is 

 pierced, these holes being often filled with stout string, by the outer 

 surface being frequently marked with whitish reticulations which are 

 more evident when the powder has been rubbed off, and by the transverse 

 surface showing a number of starlike marks, but no distinct cortical 

 layer. For an excellent figure of these marks, see Goebel und Kunze, 

 Waar., pt. ii., taf. i., fig. 2b, 3b; Hist, des Drog., vol. ii., p. 430, figs. 

 482, 486. For a microscopical structure of the root, see Berg, Anat. 

 Atlas, taf. xii. ; P. J. [3] , vol. ii., p. 841. English rhubarb in powder is 

 sometimes sold for the East Indian ; this substitution may be detected by 

 rubbing it with an essential oil and magnesia, when the powder becomes 

 pink. It is from this cause that Gregory's powder sometimes becomes 

 of a pink colour soon after being made. See P. J. [2] , vol. ii., p. 28. 

 Turmeric may be detected by moistening the powder, and then adding 

 boracic acid, which turns it red brown if turmeric be present. See P. J. 

 [3] , vol. iv., p. 354. For active principles, see P. J. [1] , vol. xvii., p. 

 572 ; vol. x., p. 39. For fluid extract, see P. J. [1] , vol. xii., p. 398. 

 For red colouring matter, P. J. [1] , vol. iv., p. 446. 



/. Rootstock. (Batavian or Dutch Trimmed Rhubarb, 



Dr. P., 206.) 



Note. This rhubarb differs only from the East Indian in having an 

 angular appearance, owing to the surface having been sliced off. It is 

 not now met with in English commerce as a distinct variety, but used to 

 be imported from Canton and Singapore. See Per. Mat. Med., vol. ii., 

 pt. i., p. 491. 



f). Rootstock. (East Indian Rhubarb.) Presented by Mr. 



Paternoster. 



Note. This specimen is peculiar by reason of the meditullium being 

 separated from the cortical portion. 



h. Root. (Canton Stick Rhubarb.) 



Note. This is probably obtained from the root branches of the 

 Chinese rhubarb plant. See Per. Mat. Med., vol. ii., pt. i., p. 491 ; P. J. 

 [1] , vol. iv., p. 446. 



432. RHEUM RHAPONTICUM, L. 



a. Root. (English Rhubarb, "fine or Turkey trimmed.") 



b. Ditto. Ditto, "East Indian trimmed." 



c. Ditto. Ditto, "Dutch trimmed." 



d. Ditto. Ditto, " small trimmed." 



e. Ditto. Ditto, " cuttings." 



Note. English rhubarb is trimmed to imitate the Russian and East 

 Indian rhubarbs, but may be detected by the absence of whitish reticula- 



