[Span. patata, potato, from the native American word (probably batata) in Hayti.] Next to the cereals or grains, the potato is the most valuable of all plants used for food. It is a native of South America, and was introduced into Great Britain by Sir Walter Raleigh in the sixteenth century. The potato plant has a portion of its stem underground, and this part sends out roots and real branches. It is at the ends of these branches that potatoes are formed. Every part of the potato plant except the tuber dies off on the approach of winter, and the tuber is the special provision made by the plant for reproduction. The eyes of the potato are real buds, and the" solid flesh of the tuber consists mainly of staicn, the destined food of the young plant. Potatoes are largely cultivated in all mild climates. There are very many varieties, differing in time of ripening, form, size, color, and quality. New varieties are raised from the seed, but potatoes are grown by planting the tubers or cuttings of them, care being taken to have at least one eye in each piece. About three-fourths of the weight of a full-grown potato is water, and of the other fourth about one-sixth is gluten and five-sixths starch.