26 KEEGAN’: CHEMICAL ANALYSIS OF CERTAIN ROSACEZ, 
the leaves are unfitted or unable to produce tannin-forming materials. 
Tormentil (Potentilla tormentilia). The modest aspect of this 
lowly, faint-peeping plant offers no betrayal of the powerfully 
efficient chemical energies which play within. The chief interest 
centres in the root, which contains a small quantity of ellagic acid, 
C,,H,O,, a large quantity of quinovic acid, C.,H,O,, and a tannin 
which is identical with the well-known astringent of the horse- 
chestnut bark, being iron-greening, yielding a phlobaphene, and not 
precipitating tartar emetic. ‘The leaves and stems contain a small 
quantity of the same tannin; and it may be noticed that when its 
lead salt is boiled with dilute hydrochloric acid, the filtrate yields 
the reactions of paracarthamin, a body allied to the colouring 
matter of blue and red flowers. Nevertheless, its quantity in leaf 
and stem is not sufficient to affect the corolla of this species. 
Meadow Sweet (Sfirea ulmaria). This is one of the most 
chemically prominent of all our common wild flowers. Its powerful 
perfume is due, not to a volatile oil, properly so called, but to an 
aldehyde of the benzoic series. When the flowers are distilled with 
water the aldehyde (salicylol), a hydrocarbon, a solid camphor, and 
a small quantity of salicylic acid are obtained. The last exists, 
ready formed, in the flowers, which also contain a tannin which 
precipitates gelatine and yields a phlobaphene; also a. yellow 
crystalline colouring matter giving the reactions of rutin. The 
leaves of the plant contain a considerable quantity of a tannin 
with reactions identical with that of tormentil root. The red 
colouring matter of the rachis of the leaf is probably the catechin 
or phlobaphene of this tannin. 
Wild Cherry (Prunus avium). The chemical analyses of the 
several parts of this eminently beautiful tree presents certain 
difficulties, but the following enumeration of their constituents is, 
I think, tolerably accurate. When the alcoholic extract of the bark 
is evaporated to dryness, the residue dissolved in hot water, and the 
solution shaken with ether, the latter extracts a substance which 
yields the reactions of phloroglucol C,H,(OH),.. This phenol is 
well-known to micro-chemical botanists, who use it extensively to 
detect the presence of lignin in vegetable tissues—the lignified parts 
(as distinguished from pure cellulose) giving with it and HCl. 
a splendid violet tint turned yellow by alkalis. ‘The tannin of the 
bark is identical with that of the horse-chestnut and tormentil. 
There is no quercitrin (rutin) in the bark, nor is there any phlorizin 
(the glucoside of the apple tree) in any part of the organism. The 
rich brown colour of the stem is due to the phlobaphene of the 
tannin combined, no doubt, as in cinchona, with a dark humus 
Naturalist, 
