284 COMPOSITA’. — 
Description.—Small annual plants with round, smooth, — 
succulent, branching stems ; leaves opposite, petioled, subcordi- 
form, subdentate. ‘The flower heads are solitary at the end of | 
pedicels longer than the leaves, of a conical form, and in 
S. oleracea as large as an acorn; they are entirely composed of 
yellow or brownish yellow hermaphrodite tubular flowers. The 
achenes are compressed with ciliated margins, and are sur- 
mounted, except in 8S. calva, by two naked awns, ‘The whole 
plant is pangent to the taste, but the flower heads are especially 
so, having a hot burning taste which causes profuse salivation. 
Chemical composttion.—Gerrard has analysed this plant with — 
the result that the active principle is an oleo-resin with power- 
fully sialagogue properties. (Pharm. Journ. March 8, 1884, 
p. 717.) R. Buchheim has found in the herb the crystalline 
alkaloid obtained by him in Pellitory root (sce article Anacylus 
Pyrethrum). We have made a full examination of the flower 
heads of Spilanthes calva, which are used as a substitute for 
pellitory in some parts of India, and we find them to contain the 
following constituents: a resin, fixed oil, yellow colouring matter, 
astringent organic acid, glucose, extractive with the odour and 
taste of malt and-7°6 per cent of mineral matter. The resin 
had the reactions possessed by pyrethrin in being soluble in 
ether, alcohol and proof spirit, insoluble in alkalies and destroyed 
by oxidizing agents. In these respects it resembles the 
pungent principle of plants found in the Zinziberacee. We 
_were unable to obtain it in a crystalline condition. The flower 
heads distilled with water afforded a distillate free from pun- 
gency, and the contents of the retort after boiling were likewise 
inert. The active principle is unstable in constitution ae 
decomposed by heat. 
ARTEMISIA VULGARIS, Tinn. var. indica- 
Fig.— Wight Ic., t- 1112; Rheede Hort. Mal. «., t. 45. 
Wormwood (Eng.), Armoise, Herbe de Saint-Jean (Fr. ). 
Hab.— ha the mountainons districts of India. 
The herb. . ras 
dys, 2 
