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IV. On Xanthoxyline, a new Crystalline jjrinciple fro77i Japanese 

 Pepper, the fruit of the Xanthoxylum piperitum o/DeCan- 

 dolle. By John Stenhouse, LL.D., F.R.S.* 



A FEW months ago I received from my friend Daniel Han- 

 bury, Jan., Esq. J a small quantity of a very singular fruit 

 from Japan, known in commerce as Japanese pepper. Mr. Han- 

 bury likewise kindly furnished me with the subjoined botanical 

 account of the tree from which it is obtained. 



" Japanese pepper is the produce of Zanthoocylum pipe7-i(nm, 

 DeCand. [Fagara piperita, Linn.), a tree of Japan of the natural 

 order Rutacece, figured and described by Ksempfer in 17l2t. 



" It consists of roundish sessile capsules of the size of a pep- 

 percorn, which appear to have been normally four in number, 

 situated at the extremity of a peduncle, though but one or two 

 are usually fully developed. The capsules, which are externally 

 reddish-brown, have their outer covering beset with numerous 

 prominent tubercles enclosing an acrid liquid to which the pepper 

 owes its pungent flavour. The seeds are black, shining, and 

 devoid of pungency ; from dehiscence of the capsules, they are 

 generally wanting in the sample which we have examined. 



" The flavour of Japanese pepper is aromatic and agreeable, 

 with a pungency not unlike that of pellitory [Radix pyrethri). 

 Its odour when bruised is remarkably fragrant. 



" It is employed as a condiment by the Japanese and Chinese." 



The Japanese pepper, after being reduced to a coarse powder, 

 was digested with successive portions of spirits of wine till it was 

 rendered nearly tasteless ; the greater portion of the spirit was 

 then drawn off by distillation, and the residue on standing for a 

 few days became filled with dark-coloiired crystals of considerable 

 size. Their colour was owing to the presence of a resinous 

 matter, which adhered to them very tenaciously. The best way 

 of removing this dark-coloured resin is to wash the crystals with 

 cold liquor ammonise, which dissolves the resin, leaving the 

 ciystals unacted on. The crystals were rendered quite white, 

 and were easily obtained an inch in length by repeatedly dis- 

 solving them in rether, or in a mixture of alcohol and sether. 



Through the kindness of Professor W. H. Miller of Cam- 

 bridge, I am enabled to subjoin the following figm'e and descrip- 

 tion of the crystalline form of xanthoxyline. 



The crystals of xanthoxyline belong to the oblique system. 



The angles between normals to the faces are : — 



* Communicated by the Author, 

 t Amanitates, pp. 892-895. 



