Further Growth and Duration of Plants 27 



turned yellow, withered away, and died. This all happened 

 in less than a year. A plant which completes its life history 

 within a year is called an Annual. Some plants take two 

 years to bear their fruit. The first year is spent in making 

 food. This is stored away as fast as it is made, usually under 

 ground. The second year a flowering shoot is sent up and 

 the food is used to ripen the seed. These are Biennials. 

 In cold countries, or where it is very hot and dry, work has to 

 stop for part of the year ; but in a mild climate the work of 

 biennials may continue without interruption, and so the seeds 

 ripen in less than two years. Many of them are found in 

 vegetable gardens. Members of the carrot family are frequently 

 biennials, though some plants of this family continue their 

 growth under ground year after year, the part above ground 

 dying down each year. This is also the habit of many 

 Pelargoiiiuins ("Geraniums"). If plants or their parts live 

 more than two years they are called Perennials. 



The underground part which stores food is sometimes a 

 stem, sometimes a root. " April Fool " {Hcdmanthus) stores 

 food in a large bulb. A bulb is a short thick stem, surrounded 

 by thick, fleshy leaves. Gladiolus Morea and their family, 

 the Irideae, usually store their food in corms. A corm is 

 a swollen stem bearing reduced leaves. The framework of 

 these leaves remains attached from year to year, and gives 

 corms of different plants distinct appearances. They are 

 called tunics. 



A white potato is a swollen stem. The '' eyes " are buds. 

 Under each bud is a scale which is a very reduced leaf. Each 

 bud can grow out into a new plant. A potato is often called a 

 tuber, but the definition of a corm fits it very well. iV sweet 

 potato gives off roots. The lower part at least is a root. The 

 upper part has more the habit of a stem, as new shoots for 

 planting are obtained from it. 



Stems, more or less swollen, which creep under ground or 

 are partly exposed, are called rhizomes. Plants with rhizomes 

 can spread without being much exposed to the sun. Bulbs, 

 corms, and rhizomes are abundant in South Africa and other 

 dry. warm countries. 



