570 ORDER 93. CONVOLVULACE^E. 



branches ; cor. tube thrice longer than calyx, segm. oval-oblong, erect-spreading ; 

 stam. barely exserted. Along rivers, S. Car., Ga., Ala. A splendid herb, 2 

 to 4f higb, its plume-like form closely beset with delicate fringe-like leaves and 

 bearing at top a long (If) thyrse of scarlet red flowers. Cor. 15" long. Jl. 

 (I pomopsis, MX. Cantua, Juss.). A more slender form found in Fla. is G. Florid- 

 ana Don. 



2 G. tricolor Bentli. TRICOLORED GILIA. St. erect, nearly smooth ; Ivs. twice 

 or thrice pinnatifid, with narrow, linear segments ; cymes paniculate, 3 to 6-flow- 

 ered; cor. tricolored, 2 or 3 times longer than the calyx, tube very short. (D An 

 elegant little garden plant, from California, If high. Fls. numerous, limb pale 

 lilac-blue, throat purple and tube yellow. \ 



4. DIAPEN'SIA, L. Calyx of 5 oval imbricated sepals, closely sub- 

 tended by imbricated bracts; corolla campanulate, imbricated in the 

 bud ; filaments 5, flat, arising from the sinuses of the corolla ; anther- 

 cells diverging at base and the dehiscence transverse ; capsule papery, 

 enveloped in the persistent calyx, 3-celled, many-seeded. Prostrate 

 undershrubs with densely imbricated, linear Ivs. and solitary terminal fls. 



1. DIAPBNSIA proper. Anthers without awns. Flowers pedicellate No. 1 



2. PYXIDANTHERA. Anthers with the lower valve awned. Flowers sessile No. 2 



1 D. Lapponica L. Caespitous; Ivs. dense, spatulate, fleshy, evergreen, obtuse 

 and entire; fls. pedunculated. 1( A little, leafy plant, 2 3' high, growing on 

 the summits of the White Mts. in N. Hampshire, forming dense tufts among the 

 rocks. Leaves crowded, pale beneath, fleshy, 5 8" by 1'' with a revolute margin, 

 clasping base, and broadly obtuse point. Fls. on slender (!' long) terminal, soli- 

 tary peduncles. Calyx of 5, obtuse leaves, longer than the leafy bracts at its 

 base. Corolla white, with 5, flat segments. July. 



2 D. barbulata Ell. Branches short, ascending; Ivs. *Jance-cuneiform, acute, 

 pubescent at base ; fls. terminal, sessile ; lower valve of the anther beaked or 

 awned at base. A prostrate, creeping plant, abundant in pine barrens, N. J. to 

 Car., forming dense beds. Stems 3 6' long, subhispid. Leaves 1 2" by \ 1". 

 Flowers white, 3" diam. Sepals denticulate, as long as the corolla tube. May, 

 Jn. The beak of the anther is variable, sometimes reduced to an acute point 

 (Pyxidanthera barbulata MX. D. cuneifolia Ph.) 



ORDER XCIII. CONVOLYULACE^E. BINDWEEDS. 



Chiefly twining or trailing herbs, sometimes parisitic, sometimes shrubby. Leaves 

 (or scales when leafless) alternate. Flowers regular, pentamerous and 5-androus. 

 Sepals imbricated. Corolla monopetalous, 5-plaited or lobed, convolute in bud. 

 Ovary free, 2 (rarely 3)-celled or falsely 4-celled, or of 2 distinct, 1-ovuled pistils. 

 Capsule 2 to 6-seeded. Embryo large, soiled in mucilaginous albumen. (Illustr. in 

 fig. 49, 56, 303, 321, 338, 455, 456> 



Genera 50, species 700, abundant in tropical climates, rare in cold. 



Properties. The roots of many species abound in an acrid, milky juice which is strongly 

 purgative. Jalap of the shops is the product of the root of Exogonium purga, of Mexico, and of 

 other species ; scammony, of Convolvulus scainmonia, native of Levant. The drastic qualities 

 of both depend upon the presence of a peculiar resin. Other species have large farinaceous 

 tubers. The Bweet Potato, a valuable article of food, is the product of C. Batatas, native at the 

 South. 



TRIBES AND GENERA. 



III. CUSCUTINEJE. Leafless, parasitic, twining. Embryo without cotyledons... CUSCUTA. 10 

 II. DICHONDRE^E. Leafy. Ova. 2, distinct, with 2 distinct styles. South... DICHONDRA. 9 

 L CONVOLVULEJS. Leafy. Ovary 1. Capsule dehiscent. Cotyledons leafy, (a) 



a Ovary 2-celled. Styles 2. Peduncle longer than the leaves STYLISMA. 8 



a Ovary 2-celled. Styles united into one. (b) 



b Calyx enveloped in 2 large bracts CALYSTEGIUM. 7 



b Calyx naked. Stamens exserted. Tube of the corolla slender CALYNYCTIOX. 6 



Stamens included. Stigmas 2, linear CONVOLVULUS. 5 



Stigma capitate IPOM^A. 4 



