418 



EXOGENOUS OR DICOTYLEDONOUS PLANTS. 



787. Ord, CactaceSB (the Cactus Family). Succulent shrubby 

 plants, peculiar in habit, with spinous buds, usually leafless ; the 

 stems either subglobose and many -angled, columnar with several 

 angles, or flattened and jointed. Flowers usually large and showy. 

 Calyx of numerous sepals, imbricated, coherent with and crowning 

 the one-celled ovary, or covering its whole surface ; the inner usu- 

 ally confounded with the indefinite petals. Stamens indefinite, 

 with long filaments, cohering with the base of the petals. Styles 

 united : stigmas and parietal placentae several. Fruit a berry. 

 Seeds numerous, with little or no albumen. All American, the 

 greater part Mexican or on the borders of Mexico. The common 

 Opuntia (Prickly Pear) extends north to New England. The mu- 

 cilaginous fruit is eatable. 



788. Ord. GrOSSUlaceae (the Gooseberry Family). Small shrubs, 

 either spiny or prickly, or unarmed ; with alternate, palmately 

 lobed and veined leaves, usually in fascicles, often sprinkled with 



714 



712 



706 



resinous dots. Flowers in racemes or small clusters. Calyx-tube 



FIG. 706. The Gooseberry (Ribes Uva-crispa) ; a branch in flower. 707. Branch in fruit. 

 708. The calyx, bearing the petals and stamens, cut away from the summit of the ovary (709), 

 and laid open. 710, 711. Sections of the unripe fruit. 712. Magnified seed (anatropous). 

 713. The same from the ripe fruit, where the raphe separates from the side of the seed, and 

 forms a part of the funiculus. 714. Longitudinal section of the same, showing the minute em- 

 bryo at the extremity of the albumen. 



