CLASS XVII. ORDER 111.) ULEX. 955 
very pale blue, and almost white; others are not unfrequently found 
of a deep pink, and these vary to a faint pink blush and almost white. 
The leaves are somewhat bitter and stimulating, and mixed with 
other fodder seems to be much relished by cattle, from which circum- 
stance it may not be improbable that it has obtained its name of 
Milkwort, as by its stimulating and provoking the appetite of the 
cattle, it will consequently produce a more abundant and healthy 
lacteal secretion. Many of the species of this genus are handsome 
and highly ornamental plants, flowering freely, and remaining in 
bloom a considerable time. Some of them are valuable medicines, 
and others furnish a kind of dye, as the P. tinetoria, found in Arabia, 
and used by the natives as a kind of indigo. The P. senega, or snake 
root, is the only species which has found its way into general use asa 
medicine in this country. It is a native of Virginia, and employed by 
the natives as a cure for the bite of the rattle snake, hence its common 
name. It was first brought into notice asa medicine in pectoral 
affections by Dr. Tennant, and has since been used with considerable 
success as an expectorant in cases of asthma, attended with difficult 
expectoration ; no medicine in such affections is more useful than a 
decoction of its roots administered in the dose of an ounce every two 
hours. The active properties of the root are found from the elaborate 
analysis of M. Queveune, to reside in an acrid which he has called 
the Polygalic acid. It was first obtained, but in an impure state, by 
Gehlen, and described by him under the name of senegin. Polygalic 
acid was administered internally to a small sized dog to the extent of 
two grains, when it produced vomiting, and four grains caused its 
death in three hours after administration. The P. vulgare, Milk- 
wort, has properties similar to this, but in a much diminished degree. 
Its action seems to be that of a stimulant to the mucus membrane of 
the stomach and bowels, and the intimate connection and sympathy 
between this and the mucus membrane lining the air passages, is the 
benefit that is derived from its administration in diminished secretions 
of that organ. 
ORDER ITI. 
DECAN'DRIA. Ten STAMENS. 
GENUS IV. U'LEX.—Linn. Furze. 
Nat. Ord. Papiniona’cE#. Linn. 
Gen Cuan. Calyx of two pieces, with a small scale on each side at 
the base, the upper lip with three and the lower with two teeth. 
Stamens monodelphous Legume turgid, one celled, two valved, 
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