452 



EXOGENOUS OR DICOTYLEDONOUS PLANTS. 



as to be quite inert ; as is also the case with the Batatas, or Sweet 

 Potato, an important article of food. To this family are appended 



847. Sllbord, Dichondreffi, Ovaries two to four, either entirely 

 distinct or with their basilar styles united in pairs. Creeping 



FIG. 921. Convolvulus purpureus. 922. The pistil. 923. Section of the capsule, and of the 

 two seeds in each cell. 924. Capsule (reduced in size), when the valves have fallen away from 

 the dissepiments ; and one of the seeds. 925. Magnified cross-section of a seed. 926. Embryo, 

 with the leaf-like two-lobed cotyledons spread out. 927. Same, with the two cotyledons sepa- 

 rated and laid open. 



FIG. 923. A piece of Cuscuta Gronovii, the common Dodder of the Northern United States, 

 of the natural size. 929. A flower enlarged. 930. The same laid open. 931. Section of the 

 ovary. 932. Section of the capsule and seeds. 933. The spiral embryo detached. 934. The 

 same in germination. 



