plants with bulbs, which are adapted, shortened, usually underground shoots. Many common monocotyledons are bulbous plants, including lilies, belladonnas, and irises. Only a few genera of dicotyledons, such as wood sorrel and coral root, have bulbs. Bulbous plants are found primarily in hot, dry regions, where during rainy seasons (usually spring but sometimes autumn) they are the predominant plant form. There are many ephemeral bulbous plants, which vegetate, blossom, and bear fruit in the course of a brief rainy season.
Bulbous plants are particularly widespread in Mediterranean countries, in southwestern Africa (snowdrop, snowflake, narcissus, and hyacinth), on the high plateaus of Central Africa (belladonna lily, Vallota, Veltheimia, and many species of Ornithogalum), in several regions of Central and South America (eucharis lily, Zephyrantes, hippeastrum, and Hymenocallis), and in the mountains of Southern Asia, Southest Asia, Middle Asia, Asia Minor, and the Caucasus (tulips, lilies, Nomocharis, and Cardiocrinum). Lilies, tulips, onions, dogtooth violets, hyacinths, snowdrops, snowflakes, squill, fritillary, and other bulbous plants grow in the USSR. Many varieties of tulip, narcissus, hyacinth, snowdrop, snowflake, squill, and fritillary are ornamentals. Some bulbous plants, for example, many species of onions, are used as vegetables. Others are used medicinally, such as the sea onion, alpine leek, and snowflake. Bulbous plants are very easy to force. Some tropical species, such as the belladonna lily and crinum lilies, can be grown as house plants.
N. I. SHORINA