SQUILL, the name under which the bulbous root of Urginea maritima, Baker, is used in medicine. The plant was formerly placed in the genus Scilla, from which it has been separated because the seeds are flat and discoid instead of triquetrous, as in the latter genus. The name of "squill" is also applied by gardeners to the various species of Scilla. The medicinal squill is a native of the countries bordering the Mediterranean, and grows from the sea-level up to an elevation of 3000 feet. The bulbs are globular and of large size, often weighing more than 4 lb. Two varieties are met with, the one having white and the other pink scales. They are collected in August, when they are leafless, the membranous outer scales being removed and the fleshy portion cut transversely into slices and dried in the sun. These are then packed in casks for exportation. They are chiefly imported into the United Kingdom from Malta. When reduced to powder and exposed to the air the drug rapidly absorbs moisture and cakes together into a hard mass. Squill has been used in medicine from a very early period. The ancient Greek physicians prescribed it with vinegar and honey almost in the same manner as it is used at present. Its medicinal properties are expectorant and diuretic. It is chiefly prescribed in bronchitis when the phlegm is tenacious and expectorated with difficulty, and in cardiac dropsy. When given in large doses it acts as an irritant poison, and its use is therefore contra-indicated in active inflammatory conditions of the mucous membrane or of the kidneys. The fresh bulb rubbed on the skin causes redness and irritation, due in part to the presence of minute crystals of oxalate of calcium.
The activity of the drug appears to be due to the active principles, scillipicrin, scillitoxin, and scillin, which were first obtained by Merck in 1878. The first has a bitter and burning taste, powerfully irritating the mucous membrane of the nose. It is soluble in alcohol and ether and partly in alkalis, but insoluble in water; if mixed with sugar it dissolves readily and can then be absorbed if injected subcutaneously. Scillitoxin is hygroscopic, very soluble in water, and has a bitter taste. These two principles have an action on the heart resembling that of Digitalis; in large doses the former stops its action in systole and the latter in diastole. Scillin is crystalline, tasteless, and soluble in alcohol, though only with difficulty in water. It is present only in very small quantity in squill, and appears to be the cause of the subsidiary effects of that drug, such as vomiting, &c.
An allied species, Urginea indica, Baker, is used in India in the same manner as the European species. The true squills are represented in Great Britain by two species, Scilla autumnalis and S. verna. The former has a racemose inflorescence; the latter has the flowers arranged in a corymbose manner, and is confined to the sea-coast. Several species are cultivated in gardens, S. bifolia and S. sibirica being remarkable for their beautiful blue flowers, which are produced in early spring. The name of Chinese squill is applied by gardeners to Barnardia scilloides and that of Roman squill to species of Bellevalia.