174-3 
DioscorEa VILLosa, LINN. DioscorEA VILLOSA, VAR. GLABRA, LLoypD. 
True Wild-Yam Root. False Wild- Yum Root. 
| Plant, under general inspection, smaller than Larger ; growing in dense clumps. 
the next ; isolated. 
Leaves more sharply pointed, almost aristate ; Sharply pointed ; absolutely glabrous. 
densely short pubescent beneath. 
Rhizome horizontal, about % inch in diameter, This rhizome resembles greatly that of Collin- 
oval, flattened above and below, seldom branched, sonia Canadensis. It is found in thick, matted, 
but decidedly tubercled by small protuberances rough clumps, the main portion contorted by the 
that appear like abortive attempts to branch ; the procession of branches, which are in themselves 
upper surface is marked at intervals of about an knotty and of the full diameter of the rhizome- 
inch with the scars of previous years’ stems. axis itself; these branchings issue at an acute angle 
forward, and themselves bear for the most part the 
cup-shaped scars of former stem-growths. 
My herbarium contains three female and four male plants in flower, and one 
fruiting specimen, representing the States of New York, Pennsylvania, Ohio, Vir- 
ginia, and Georgia,—all sent to me by botanists, who designated each as D. villosa; 
according to the above differentiation, two of the females and one male,as well as 
the fruiting specimen, are var. glabra, Lloyd. 
Dioscorea has held a place in domestic and general practice for a long period 
as almost specific in certain forms of bilious colic, in which it is promptly effica- 
cious; it is also considered diaphoretic, emetic, and expectorant. As a visceral 
antispasmodic, and remedy for intestinal irritations, it has proved itself a valuable 
remedy in cholera morbus, spasm of the diaphragm, spasmodic asthma, dysmenor- 
rhoea, and kindred afflictions. 
Although the leaves of the chestnut are officinal in the U. S. Ph., the root of 
this valuable plant is not. In Eclectic Practice, the following preparations are 
used: Decoctum Dioscoree, and Extractum Dioscoree. 
PART USED AND PREPARATION.—The fresh root of either form, that of the 
first year preferred, is gathered in September, and chopped and pounded toa pulp 
and weighed. Then two parts by weight of alcohol are taken, the pulp thoroughly 
mixed with one-sixth part of it and the rest of the alcohol added. After stirring 
the whole well, it is poured into a well-stoppered bottle, and allowed to stand for 
eight days in a dark, cool, place. 
_ The tincture separated from this mass by straining and filtering, should have a 
deep amber color by transmitted light; a cherry-like odor; a taste at first woody, 
then bitter, and an acid reaction. 
CHEMICAL CONSTITUENTS.—Dioscorea roots contain, without doubt, an 
acrid principle, resin, and starch, but as yet they have not been isolated. Dios- 
coretn is not a principle, it being simply an extract embodying the solid constitu- 
ents of the fluid extract of the root. 
PHYSIOLOGICAL ACTION.—The experiments of Drs. Cushing and Bae : 
with doses of from 5 drops of the tincture to 200 drops of the fluid extract, gave 
essentially the following symptoms of disturbance: Vertigo and dizziness; heavi- 
ness and aching of ira! head; : 
: smarting a and soreness of ae os : irritation and oe 
