Arum.—Indian Turnip.

Fig. 30. Arisaema triphyllum. Photo: Arisaema japonicum. The partially dried corm of the Arisaema triphyllum, Torrey (Arum triphyllum, Linné).
Nat. Ord.—Araceae.
COMMON NAMES: Indian turnip, Jack-in-the-pulpit, Dragon-root, Wake-robin.
ILLUSTRATIONS: Willdenow, Sp. Plant IV, 480, as Arum triphyllum; also as same in Bigelow, Amer. Med. Bot. I, 52; Johnson's Med. Bot. of N. A., 263.

Botanical Source.—Indian turnip has a round, flattened, perennial, rhizome (cormus), the upper part of which is tunicated like the onion, the lower and larger portion tuberous and fleshy, giving off numerous long, white radicles in a circle, from its upper edge; the under side is covered with a dark, loose, wrinkled epidermis The spathe is ovate, acuminate, convoluted into a tube at the bottom, flattened and bent over at the top like a hood, varying in color internally, being green, dark-purple, black, or variegated with pale-greenish stripes on a dark ground, supported by an erect, round, green, purple, or variegated scape, invested at the base by the petioles and their acute sheaths. The spadix, situated within the spathe, is club-shaped, shorter than the spathe, rounded at the end, green, purple, black, or variegated, contracted into a narrow neck at the base, where it is surrounded by the stamens or ovaries. In the fertile plants it is invested with roundish, crowded ovaries, each tipped with a stigma; in the barren its base is covered with conical, fleshy filaments, each bearing from 2 to 4 circular anthers. Plants which are perfectly monoecious, and which are the least common, have stamens below the ovaries. The upper portions of the spadix wither, together with the spathe, while the ovaries grow into a large, dense bunch of shining berries of a bright scarlet color. The leaves, generally one or two, are ternate and stand on long, sheathing footstalks. The leaflets are oval, mostly entire, acuminate, smooth, paler on the under side; becoming glaucous as the plant grows, the two lateral ones being somewhat rhomboidal.

Description and History.—The corm is subglobular, depressed, or turnip-shaped, from 1 ⅔ to 2 ½ inches in diameter. The base is free, flat and corrugated, while the upper portion has a zone of rootlets surrounding the corm. Within it is milky-white, amylaceous, or mealy, while externally it is of a dark, brownish-gray color. It has no odor, and possesses an acrid, burning taste. When first dug it is fiercely acrid—too much so for internal employment; upon masticating it, it causes a persistent and intensely acrid impression upon the tongue, lips, and fauces, like that of a severe scald, with considerable prickling, and which is followed by slight inflammation and tenderness. Milk relieves this sensation, greatly modifying its intensity. It exerts no such influence upon the external skin, except upon long and continued application. The ordinary solvents, ether perhaps excepted, do not extract the acrid element, which is exceedingly volatile, the root rapidly losing its acrimony by age. It should always be used when partially dried. Its activity may be preserved for a year or more by burying the root in sand. This plant inhabits the American continent, in both hemispheres, being found in wet locations, and flowers from May to July. The whole plant is acrid, but the root is the only part employed.

Chemical Composition.—In addition to its acrid principle it contains a large proportion of starch; also, gum, albumen, saccharine matter, calcium and potassium salts, and extractive. When the acrid property is driven off by heat, the root yields a pure, delicate, amylaceous matter, resembling the finest arrowroot, very white and nutritive. That raphides of oxalate of calcium give to the corm its acridity has been asserted by Weber (1891).

Action, Medical Uses, and Dosage.—(For action of the fresh root see above.) Acrid, expectorant, and diaphoretic. Recommended in flatulence, croup, whooping-cough, stomatitis, asthma, chronic laryngitis, bronchitis, pains in the chest, colic, low stage of typhus, and various affections connected with a cachectic state of the system. Externally it has been used in scrofulous tumors, tinea capitis, and other cutaneous diseases. Its action in the prostration of low fevers with wild delirium is due to its effects upon the cerebral centers. It is reputed useful in cerebro-spinal fever and scarlatina, when delirium is present, when the tongue is swollen, red, and painful, and the buccal membranes inflamed. Chronic laryngitis, or minister's sore throat, with sudden hoarseness and aphonia, is specifically influenced by arum. It is also useful in ulceration of the larynx and pharynx. It is a good remedy, internally and locally, for aggravated red sore throat. The powdered root may be given in 10-grain doses, increased, if required, to 20 or 30 grains, and repeated every 3 or 4 hours. It may be taken in sweetened mucilage, syrup, or honey. Specific arum, 1/10 to 10 drops. Its specific effects are best obtained by minute doses of the specific arum—1/10 to ½ drop doses.

Specific Indications and Uses.—Hoarseness and aphonia, with burning and constriction of the throat, and thin, ichorous, nasal discharge; intensely sore throat, with bleeding and fetor; a feeling of fullness or swelling of the mouth, throat, and tongue, the latter being red and sensitive.

Photo: Arum maculatum 1. Related Species.Arum maculatum, Linné, Cuckoo-pint.—Europe. This plant is somewhat similar to Indian turnip, possessing the same chemical components, with the addition thereto of saponin, fixed oil, and resin. Large doses of it have produced inflammation of the bucco-oesophageo-gastric tract, and fatal effects are recorded from its use. In times of famine the peasants have used the prepared corm in making bread. Small amounts of a starchy material were at one time prepared from it on the Isle of Portland, England, and sold on the market as "Portland sago" or "Portland arrowroot". It was formerly official in the Dublin Pharmacopoeia.

Colocasia antiquorum, Schott. (Arum Colocasia [esculentum], Linné. Caladium acre, Robert Brown. Caladium esculentum, Ventenat). The Fijian "Taro." This plant is cultivated in the Levant for its leaves, which are eaten like spinach (Treasury of Botany). The root well cooked is eaten by the Fijis. They call it taro and prefer to eat it cold. The whites prefer it roasted and served hot. These roots are largely used in Japan for food, having been catalogued in a Japanese exhibit in London as "Japanese potatoes" (Maiden, Nat. Plants of Australia). Styptic and astringent. Tubers used in India as fomentations in rheumatism. A single application of the juice of a slightly roasted petiole checks otorrhoea in children (Dymock, Mat. Med. Western India). The same arrests arterial hemorrhage (Pharm. India). Cultivated in gardens in the United States for decorative effects.

Colocasia macrorrhiza, Schott. Tubers baked or roasted in cakes called hakkin, and used as food by the Queensland natives.

Typhonium Brownii, Schott. (Arum orixense, Robert Brown). New South Wales to North Australia. Used as food like the Colocasia macrorrhiza.

Richardia aethiopica, Kunth. (Calla aethiopica, Linné.) Egyptian calla. The starchy tuber of this ornamental plant has been used as food.

Raphidophora vitiensis, Seemann. Nat. Ord.: Araceae. Fiji Islands. Source of Tonga, which is a mixture of leaves, bark, and fibrous wood sent to market tied up with cocoanut fiber. The stem of the tree is scraped to obtain the drug. It contains starch, raphides, potassium chloride, and tongine, a volatile alkaloid. Introduced by Ringer and Murrell as a remedy for neuralgia. The bark in the above mixture comes from a tree of another order (Verbenaceae)—the Premna taitensis, De Candolle. It contains fat, volatile oil, sugar, and pectin (Gerard).

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