266 PRACTICAL BOTANY. 



868. Ovary superior 870 



Ovary inferior 8G9 



869. A low, straggling shrub. Calyx 5-cleft, with the 

 lobes recurved, and a 5-glandular disk in the bottom. Sta- 

 mens 5. Style short and thick. Fruit fleshy, drupe-Hke, 

 pear-shaped. Pyriilaria oleifera, Gray. 



Large trees. Calyx small, 5-parted. Stamens 

 5-10, etc 859 



870. Stamens 9, in 3 rows, the inner set usually gland- 

 bearing at the base, in the sterile flowers ; and 6, or 12-18 

 rudimentary ones in the fertile kind. Calyx 6-parted. 

 Trees or shrubs 871 



Stamens 4. Calyx 4-parted. Ovary 2-celled, one 

 of the cells smaller and disappearing. Achenium ovate, com- 

 pressed, covered by the succulent calyx, the whole fertile spike, 

 therefore, converted in fruit into an oblong, juicy, aggregate 

 (blackberry-like, dark purple) berry, or sorosis. Leaves 

 ovate, heart-shaped, serrate, often 3-lobcd. Shrubs or small 

 trees. (795) Morus. 



871. The axillary clusters or umbels of flowers sur- 

 rounded by a 2- to 4-leaved involucre. Fertile flowers with 

 12-18 rudiments of stamens. Flowers preceding the leaves. 



872 

 Involucre none. An there of the sterile kind 4- 

 celled, 4-valved. Fertile flowers with 6 short rudiments of 

 stamens and an ovoid ovary. Leaves many of them ovate 

 and entire, and some 3-lobed. Flowers appearing with the 

 leaves. Drupes blue, on red pedicels. 



(702) Sassafras officinale, Nees. 



872. Anthers 2-celled, 2-valved. Involucre 4-leaved. 



(703) Benzoin. 

 Anthers 4-celled, 4-valved. Involucre 2- to 4- 

 leavod. Branchlets zigzag. 



(703) Tetranthera geniculata, Nees. 



873. (864.) Scales of the aments irregularly cut-lobed at 

 the ai^ex. Stamens (8-12), as well as the ovary, surrounded 

 below by a cup-shaped, perianth-like disk. Styles 2, bifid. 

 Pod 2-valved. Seeds clothed with woolly down. 



Populus, Tourn. 



