NATURAL ORDEES. 263 



pendulous. Fridt indehiscent, crowned by the adhering calyx. 



Seed solitary, destitute of albumen. 



a. Properties : the bark is astringent, used as a febrifuge and for tanning ; the 

 A-uit is sweet and edible. 

 Gexus. — Rhizophora. 



451. ONAGRACEiE, the Evening Primrose Tribe. — Herhs ,or 

 sJiruhs. Leaves simple, alternate or opposite. Calyx tubular, 

 adherent to the ovary. Petals usually 4 (rarely 3 or 6), in- 

 serted into the tube of the calyx. Stamens as many as the 

 petals, or twice as many ; filaments distinct ; pollen triangular, 

 usually cohering by threads. Ovary 2-4-celled ; styles united. 

 Fruit capsular or succulent. Seeds without albumen ; eiiibryo 

 straight. 



a. Properties : some species yield edible fruits and seeds, many are mucilaginous, 

 a few are astringent. 



Genera. — Jussieu, Ludwigia, (Enothera, Clarkia Epilobium, Fuchsia, Gaura, 

 Circaea. 



452. Sub-order, HALORAGEiE. — Aquatic fierhs., or U7ider shrubs^ 

 often apetalous. Seeds solitary, furnished with little albumen, 

 as in Myriophyllum and Hippuris, where the limb of the calyx 

 is almost wanting ; petals none ; stamens reduced to a single 

 one ; the ovary 1-celled. 



Genera. — Hippuris, Myriophyllum, Serpicula, Proserpinaca. 



453. Cactace^, the Cactus Trihe. — Succulent shrubs., with 

 angular or flattened stems and spinous buds, often leafless. 

 Flowers mostly large and showy. Sepals numerous, the inner 

 confounded with the petals. Stamens indefinite ; filaments 

 long, cohering at the base with the sepals and petals ; anthers 

 ovate, versatile. Ovary fleshy ; ovules attached to parietal 

 placentas equal in number to the stigmas ; style filiform. Fridt 

 succulent, 1-celled. Seeds numerous, without albumen ; embryo 

 straight, cm'ved, or spiral. 



a. Properties : fruit mucilaginous, eatable. 

 Genus. — Cactus. 



454. Grossulace^, the Currant Trihe. — Small shrubs. Leaves 

 alternate, lobed. Flowers in racemes or small clusters. Calyx- 

 tube adherent to the ovary, 5-lobed, sometimes colored. Petals 

 minute, alternate with the segments of the calyx. Stamens 5, 

 inserted on the calyx. Ovary 1-celled. Fruit a berry, crowned 

 with the remains of the flower. Seeds immersed in pulp, and 

 attached to two, opposite, parietal placentas ; albumen horny ; 

 embryo straight, minute. 



a. Properties : fruits edible, sometimes containing malic acid. 

 Genus. — Ribes. 



455. LoASACEJE. — Herbs^ usually clothed with rigid or gting- 



