232 SYSTEMATIC BOTANY. 



3. C. CITRULLUS (Water-melon). Stem slender, prostrate, trailing, 

 hairy ; leaves palmately 5-lobed, very glaucous beneath ; flowers yellow, 

 solitary ; fruit smooth, marked with various shades of green, very juicy. Cul- 

 tivated. June- August. 



3. Cucurbita. Flowers monoecious. Corolla campanulate. Petals 

 united and cohering with the calyx. STERILE FLOWERS Calyx 5- 

 toothed. Stamens 5, triadelphous, with united, straight anthers. FER- 

 TILE FLOWERS Calyx 5-toothed. Stigmas 3, thick, 2-lobed. Pepo 

 fleshy or woody, 3-5-celled. Seeds obovate, smooth, with thickened 

 margins. 



C. PEPO (Pumpkin). Plant rough and hispid ; stem procumbent ; ten- 

 drils branched ; leaves very large, cordate, palmately 5-lobed ; flowers large, 

 axillary, yellow ; sterile ones on long peduncles ; fruit very large, roundish, 

 and yellow when ripe. Common in cultivation. July. 



Order XXX VIII. CACTACE^E (Cactus Family^. 



Succulent, shrubby plants, almost always destitute of leaves, 

 and producing spinose buds. Stems usually angular, or flattened. 

 Flowers sessile, showy. Sepals numerous, forming a tube, which 

 adheres to the ovary, completely inclosing it. Petals indefinite, 

 often passing into the sepals, inserted into the calyx-tube over the 

 summit of the ovary. Stamens indefinite, attached to the petals, 

 with long filaments and versatile anthers. Ovary i -celled, fleshy. 

 Style single, forming a stellate cluster with several anthers. Fruit 

 a many-seeded berry. 



Opuntia. Sepals and petals numerous, united in a tube which 

 adheres to the ovary. Stamens numerous, shorter than the petals. 

 Style cylindrical, with numerous, thick, erect stigmas. Berry prickly, jj. 



O. VULGARIS (Prickly Pear). Prostrate, creeping, with articulated 

 branches and broad and flattened joints, with fascicles of prickles regularly 

 arranged ; prickles short and numerous, each fascicle usually consisting of 

 several strong subulate spines ; flowers yellow ; fruit crimson, nearly smooth, 

 eatable. In sandy fields. June-July. 



Order XXXIX. UMBELLIFER^E. 



Herbs, rarely suffrutescent. Stems usually hollow and fur- 

 rowed. Leaves alternate, usually compound, the petioles becom- 

 ing dilated, and sheathing at base. Flowers in umbels, usually 

 with an involucre. Calyx adherent to the ovary, the very small 

 border 5-toothed, or entire. Petals 5, usually with an inflexed 

 point, inserted between the calyx-teeth in a disk which crowns 



