DICOTYLEDONOUS PLANTS 



333 



monoecious, dioecious or rarely perfect; calyx regular; stamens 

 (when present) equal in number tO' the lobes of the calyx and 

 opposite them ; ovary one-chambered, 

 onercap>suled ; fruit an. achene or 

 a drupe, sometimes many fruits 

 uuit^ into a mass. A large fam- 

 ily of diversified characters, mostly 

 tropical. 



The elms (Ulmiis), of which 

 there are several species, are good 

 types of this family in which the 

 fruit is developed as a samara (Fig. 

 169). The American hackberry 

 (Celtis occidentalis) is another 

 familiar American tree ; the com- 

 mon hop {Humulus lupulus) is a well-known vine which is 

 grown to some extent for its bitter and aromatic principles. 



The American red mulberry (Moms rubra) and the Asiatic 



Fig. 168. — Bur of native -chest- 

 nut showing two seeds within. (Pro- 

 ductive Plant Husbandry.) 



Fig. 169. — Flower of elm. 



white mulberry (M. alba) are well-known fruits. The silkworms 

 feed upon the leaves of the' latter, which is grown eJrtensively 

 for that purpose (Fig. 170). 



