474 



ILLUSTRATIONS OF THE NATURAL ORDERS. 



celled (sometimes two-celled) ovary and the always one-celled and 

 one-seeded fruit, but sometimes enclosing it. Stamens as many as 

 the lobes of the calyx and opposite them, or sometimes fewer. Em- 

 bryo large ; cotyledons mostly broad ; the radicle superior in the 

 fruit. Stipules often deciduous. A large and greatly diversified 

 order, comprising at least four well-marked suborders. 



912. Suboi'd. UJmaces {Elm Family). Trees or shrubs, with a 

 watery juice, alternate rough leaves, perfect or merely polygamous 

 flowers, two styles or stigmas ; the ovary either one- or two-celled, 

 ■with one ovule suspended from the summit of each. Fruit either a 

 samara (Fig. 578), with a straight embryo and no albumen, as in 



the Elm (Uhnus) ; or a drupe with a curved embryo and scanty 

 albumen, as in Celtis (Hackberi-y), the type of the tribe Celtide^e. 

 Timber-trees. The inner bark of the Slippery Elm is highly 

 charged with mucilage. Hackberries are edible. 



913. Subord. ArtOCarpeae {Bread-fruit Family) ; which are chiefly 

 tropical trees or shrubs with a milky or yellow juice ; the monoj- 

 cious or dioecious flowers mostly aggregated into fleshy heads, and 



FIG. 1156 Flower of the Slippery Elm. 1157. Calyx laid open and the oyary divided yer- 

 tically. 1158. Fruit, the cell laid open to show the single seed. 1159. The latter magniGed 

 1160. Its embryo. 



FIG. 1161. Branch of Celtis Americana, in flower. 1162. Enlarged flower, divided yerti- 

 cally. 1163. Drupe, the flesh divided to show the stone. 1163'. The coiled embryo. 



