EXOGENOUS OR DICOTYLEDONOUS PLANTS. 



421 



veined leaves, usually in fascicles, often sprinkled with resinous dots. 

 Flowers in racemes or small clusters. Calyx-tube adherent to the 

 one-celled ovary, and more or less produced beyond it, five-lobed, 

 sometimes colored. Petals (small) and stamens five, inserted on 

 the calyx. Ovaiy with two parietjil placentte : styles more or less 

 united. Fruit a many-seeded berry. Embryo minute, in hard 

 albumen. — Ex. Ribes (Gooseberry and Currant). Never unwhole- 

 some : the fruit usually esculent, containing a mucilaginous and sac- 

 charine pulp, with more or less malic or citric acid. Two or three 

 red-flowered species of Oregon and California, and the Yellow or 

 Missouri Currant, are oi'namental in cultivation. 



824. Ord. CaclaccfC {Cactus Family). Succulent shrubby plants, 

 peculiar in habit, with spinous buds, usually leafless : the stems 

 either globular and many- 

 angled, columnar with several 

 angles, or flattened and joint- 

 ed. Flowers usually large 

 and showy. Calyx of sev- 

 eral or numerous sepals, im- 

 bricated, coherent with and 

 crowning the one-celled ova- 

 ry, or covering its whole sur- 

 face ; the inner usually con- 

 founded with the indefinite 

 petals. Stamens indefinite, 



with long filaments, cohering ^^^^^V^ /i_/ 



with the base of the petals. 

 Styles united : stigmas and parietal placentas several. Fruit a 

 berry. Seeds numerous, with a curved or fleshy and rounded em- 

 bryo,-and 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 : its mucilaginous 

 fruit is eatable. So is the SAveet red pulp of the huge Cereus gigan- 

 teus of Sonora and South California, which forms a singular tree, 

 forty or fifty feet high. Cereus grandiflorus is the magnificent 

 Nijiht-blooming Cereus. 



825. Ord. LoasaceaP. Ilei-bs usually clothed with rigid or stinging 

 hairs ; leaves opposite or alternate, without stipules ; the flowers 

 showy. Calyx-tube adherent to the one-celled ovary ; the limb 



FIG. 888. Flower of Mamillaria csespitosa, of the Upper Slissouri. 



3G 



