BY MEANS OF THE PYRETHRUM. 537 



and also jalap, cockle, of Levant, nux vomica, and even arsenic, enter 

 into tlie composition of the powders we have examined. 



It was not till 1856 and after many efforts that we could procure some 

 good seeds of the Pyrethrum of Caucasus. We were then able to ex- 

 tend our researches as to the culture of the plant. We had to proceed 

 cautiously in determining the soil best adapted to it, to find out the best 

 exposure and to discover the care necessary to be bestowed on it. The 

 first sown on Sejrtember 15, 1856, produced only a few shoots. A great 

 point was, to ascertain whether the plant was an annual or perennial. 

 In order to determine this, several of the procured plants passed through 

 the winter of 1856-57, and sustained from 8 to 12 degrees of cold with- 

 out appearing to suffer. 



The seeds gathered from this first culture were sown in February, 

 1858. In May, we communicated our experiments and the success that 

 had crowned them to Messrs. Decaisne, Neumann, and Pepin. These 

 gentlemen then examined the plant botanically, and their opinions are 

 as follows : — 



Botanical characters. — The genus Pyrethrum * has been established 

 by Qaertner, according to Haller. Linnaeus classes it under the genus 

 Chrysanthemum, but it differs from the latter by the strap-shaped flowers 

 or semi florets situated on the circumference and terminating by three 

 teeth, and because its fruits or akenes are crowned by a projecting mem- 

 brane frequently toothed. 



It must be admitted that these characteristics are not always very 

 distinctly marked in some of the numerous species composing the Pyre- 

 thrum ; and that the other characteristics of these plants resemble in 

 every respect those of the Chrysanthemum. However this may be, 

 present authors unanimously adopt the genus Pyrethrum. It belongs to 

 the great family of the composite plants in the tribe of Seneciones, and 

 the subdivision of Anthemidese. 



After the introduction into France, in October, 1857, of the first 

 shoots of the species dwelt upon in this paper, there was. a long period 

 of indecision as to the true name which was to be given to it. On its 

 presentation to the Imperial and Central Society of Horticulture, it 

 was regarded as Pyrethrum roseum, Biebers ; (Chrysanthemum roseum, 

 Adam ;) but at that time the characters of the plant not being per- 

 fectly ascertained, this decision could only be the result of a supposition. 

 Later when we presented some flowering specimens of the plant to the 

 Museum, M. Decaisne believing that he was examining a plant well- 

 known to the botanical explorers of the Caucasus, and described in 

 botanical works in that region, at first sight took it for Pyrethrum 

 pedunculare. 



Shortly afterwards, having inspected the herbariums of the Museum, 



* The name is a Greek word, signifying "fire," because the first plant of this 

 name had a root which, when chewed, leaves a very burning taste in the mouth. 

 It is a species of chamomile (Anthemis pyrethrum), used in medicine. 



