Hydrocotyle.—Water Pennywort.

The entire plant of Hydrocotyle Asiatica, Linné.
Nat. Ord.—Umbelliferae.
COMMON NAMES: Water pennywort, Thick-leaved pennywort, Indian pennywort, Bevilacqua.
ILLUSTRATION: Bentley and Trimen, Med. Plants, 117.

Botanical Source and History.—The genus Hydrocotyle is an extensive family, comprising nearly 100 species that are found throughout the temperate world, consisting mostly of small, inconspicuous marsh herbs. The generic characters are: Flowers small, in simple umbels; petals 5, white, the points not inflexed; calyx margin wanting; fruit of 2 carpels, which are flattened laterally, 5-ribbed, and not furnished with oil-tubes.

Hydrocotyle Asiatica is a low, creeping plant, widely diffused over the warmer parts of the world, and abundantly met with in India, Cape of Good Hope, and Australia. The leaves are kidney-shaped, crenate, and the petioles attached at the base of the leaf.

In England the genus is represented by a single species, H. vulgaris, which is found growing in most parts of Europe. The leaves of this species are nearly orbicular, and about the size of an English penny; hence the common name "pennywort." The name "sheep-rot" is sometimes applied from the supposition that it causes the "rot" when eaten by sheep. The leaf-stalks are attached to the leaf-blade near the center of the under surface, a position comparatively rare among plants.

There are five American species of Hydrocotyle, all small herbs, growing in swamps. H. umbellata and H. interrupta have the leaves peltate; while in H. Americana, H. ranunculoides, and H. repanda the leaves are attached to the leafstalks at the base of the blades. Hydrocotyle Americana is the most common native species, and is found farther north than the others. It is a delicate, slender plant growing in damp, shady places; the leaves are thin and smooth, and are borne on short leaf stalks; the minute white flowers are in close sessile umbels, in the axes of the leaves. The Hydrocotyle vulgaris and the 5 American species have properties probably similar to those of the H. Asiatica.

Medical History and Chemical Composition.—In 1852, Dr. Boileau, of India, having been for many years afflicted with leprosy, heard that the American plant, called Chinchunchulli, was of value. This plant was said to resemble the violet, and, while waiting for the arrival of a supply, the doctor experimented with Hydrocotyle Asiatica, and recovered. He subsequently used the remedy with other lepers. His experience was published, the plant being called Bevilacqua.

In 1853 or 1854, M. Jules Lepine continued the subject in the Madras Gazette (Pharm. Jour. and Trans., 1853 and 1854), and confirmed the assertions of Dr. Boileau regarding its efficiency in leprosy. Before this, however, the plant is said to have occupied a place in the Indian Materia Medica. The composition of the plant is not known, beyond the experiments of Lepine, who decided that an oily substance, named by him vellarin, was the active medicinal principle. (See Christy, New Commercial Plants, 1885, p. 58.)

Action, Medical Uses, and Dosage.—This plant should be ranked among the acronarcotic poisons, along with the Oenantha crocata, and the Cicutas. Boileau, Lepine, and others have found it useful as a remedy against elephantiasis of the Greeks (leprosy). Devergie, Cazenave, Waring, Hunter, etc., have derived benefit from it in chronic eczema and other cutaneous maladies, in scrofula, secondary syphilis, ulcers, and chronic rheumatism. It is an active agent, large amounts inducing headache, dizziness, and stupor, as well as bloody passages from the bowels. Itching of the skin is said to be occasioned by it also. As the root is very hygroscopic, and is not well preserved in powder, its best form for administration is in infusion, or syrup, 1 ounce of the root to 1 pint of fluid, and which may be given in doses of from ½ to 1 fluid ounce, repeated 3 or 4 times a day. An alcoholic extract may likewise be used in doses of from ¼ to ¾ of a grain. Notwithstanding the favorable reports concerning the efficiency of this plant, it has fallen into disuse, and is seldom employed at the present day.

The Hydrocotyle gummifera, growing in Brazil and in the Antilles, has been used in hepatic and renal affections.

King's American Dispensatory, 1898, was written by Harvey Wickes Felter, M.D., and John Uri Lloyd, Phr. M., Ph. D.