Lettuce, or Lactuca, L. a genus of plants comprising 15 species, two of which are natives of Britain : the principal of these is the virosa. Wild or strong-scented Lettuce, that abounds on chalky soils, and dry banks of ditches ; flowers in the months of August and September. It has a strong odour, not unlike that of opium, and is possessed of similar narcotic properties, that reside in its milky juice; small doses of which, newly expressed from the plant, are recommended in the dropsy. It is said to agree with the stomach, to allay thirst, and to be mildly laxative.
Several other species and varieties of the Lettuce have, at different times, been introduced into Britain, and are now cultivated for culinary purposes. The principal of these are: 1. the Common or Garden Lettuce, which is propagated from seeds that are generally sown early in the spring, that the plant may be cut and mixed with other salads. In its more cultivated state, this kind is known by the name of Cabbage Lettuce. 2. The Silesian. 3. The Imperial. 4. The Royal Black ; and, 5. the Upright White Cos-Lettuces, which are the most valuable plants of this nature, now reared in our gardens. They' are likewise raised from seed, which should be sown towards the end of February, or in the beginning of March, on a warm light soil, and in an open situation. As soon as the plants shoot forth, it will be necessary to thin them, so that they may be 15 inches apart in every direction, after which they will only require to be carefully weeded ; weeded ; and, as the Black Cos-Lettuce grows large, it will be necessary to tie its leaves together, in order to whiten the inner part.
There are two other sorts, known under the name of Dutch brown and Green Capuchin Lettuce, which may be sown late, under walls; being very hardy, they withstand the severity of the winter, and will be valuable when no other green salad can be procured.— BEChstein states a curious fact, which deserves to be recorded, namely, if the two varieties last mentioned be planted together, and suffered to bear seeds, in a rich, warm, but moist soil, the future produce of such seed will be a new and very excellent kind of this plant, forming extraordinary large heads,' the leaves of which are sprinkled with deep red spots, and uncommonly tender.
Properties :—The various kinds of garden-lettuce are emollient, cooling, and wholesome salad-herbs ; they are easy of digestion, -somewhat aperient, and supposed to possess a soporific quality : there is no doubt, that by abating heat, and relaxing the fibres, they in many instances contribute to procure rest. But, for this purpose, lettuces should not be eaten with oil and vinegar, as the former renders them less digestible; but, if either or both of those condiments must be used, it Will be advisable to add sugar, which will counteract the rancid nature of the oil: though simple salt is the most proper spice for salads.