151 ANACYCLUS PYRETHRUM 



lengtli_, and from ^ an inch to nearly } of an inch in thickness. 

 The pieces are straight or slightly curved, cylindrical or some- 

 what tapering, and occasionally crowned above by the remains of 

 leaves ; they are unbranched, but are sometimes furnished with a 

 few hair-like rootlets. The external surface is brown, rough, 

 shrivelled longitudinally, and marked by numerous dark-coloured 

 receptacles of resin. Pellitory root is brittle, and breaks with a 

 close, compact, resinous fracture ; the fractured surface shows no 

 trace of pith, but presents a radiated appearance from the large 

 size of the medullary rays, and is marked by numerous dark- 

 coloured receptacles of resin. It has no very evident odour, only 

 feebly aromatic ; and but little taste at first, but when chewed, 

 it excites a singular burning and pricking sensation over the 

 whole mouth and throat, which remains for some time, and causes 

 a copious flow of saliva. 



Pellitory root has been frequently analysed, and its activity 

 proved to reside in an acrid matter, called by Parisel pyrethrin. 

 But this so-called pyrethrin is, in reality, a mixed substance, 

 consisting, according to Koene, of a brown acrid resin, which is 

 probably the more important principle, and the one in which the 

 activity of the root essentially resides ; of an acrid brown fixed oil, 

 and a yellow acrid oil. The root also contains inulin in large 

 proportion, a little volatile oil, gum, a trace of tannic acid, and 

 other constituents of no particular importance. 



Medical Properties and Uses. Pellitory is a powerful irritant 

 and sialagogue, and when applied to the skin, it acts as a rube- 

 facient. It is rarely or ever given internally ; but is chiefly used 

 as a masticatory, or in the form of a gargle prepared by diluting 

 the official tincture with water. As a masticatory it has been 

 found useful in toothache, aphonia, paralysis of the tongue 

 and muscles of the throat, and in neuralgic affections of the teeth, 

 &c. As a gargle it is often employed with advantage in relaxa- 

 tion of the uvula or tonsils, and in other cases. A few drops of 

 the tincture are also sometimes applied on cotton wool to the 

 cavity of a decayed tooth for the relief of toothache. A recent 

 case reported in the Practitioner shows the necessity of exercising 



