302 TEXTBOOK OF BOTANY 



and pistils are usually borne in separate flowers ; in some 

 species the two kinds of flowers grow on different plants, in 

 others on the same plant. The fruits are one-seeded, and 

 are often nuts or stone fruits. The nettles, which give the 

 family its name, are unpleasantly familiar weeds. The white 

 mulberry is important because its leaves are used as food for 

 silkworms. Its berries, like those of other mulberries, are 

 edible. It is a native of China and has been cultivated in 

 Mediterranean countries since the twelfth century. The 

 white, black, and red mulberries are used also as shade trees. 

 The osage orange, much used for hedges, is a close relative 

 of the mulberries. The six hundred species of the genus 

 Ficus are mostly tropical ; Ficus elastica is the india-rubber 

 tree, the most important source of rubber in the eastern 

 hemisphere. " Rubber plants," common house plants in 

 colder climates, are small specimens of this tree. The banyan 

 tree belongs to the same genus, as does also the cultivated 

 fig tree. The hop and the hemp are important raembers of 

 the nettle family ; the hemp is widely cultivated for its 

 bast fibers which are used in making ropes and cloth. The 

 hemp also supplies birdseed ; the drug known as hashish is 

 made from its flowers and leaves, and the drug cannabis 

 from the dried flowering tops of the pistillate plants. The 

 Asian plant that furnishes the fiber known as " ramie " or 

 " China grass " is a member of the family. Another is the 

 breadfruit tree, and another the upas tree of the East Indies, 

 whose juice is used by the natives for the poisoning of arrows, 

 and in regard to whose poisonous influence many extravagant 

 tales used to be told. Several tropical members of the 

 family besides Ficus elastica are sources of rubber. 



311. The Goosefpot Family. — This is a small family 

 whose members are mostly herbs living in prairies or waste 

 places, many of them with fleshy leaves. The flowers are 

 small and inconspicuous and are borne in large numbers in 

 branched, spike-like clusters. The common edible beet, the 



