CONVOLVULACE^E. (CONVOLVULUS FAMILY.) 333 



ornament, and one, the Sweet Potato, for its edible farinaceous roots : those 

 of several species are cathartic ; e. g. Jalap.) There are three suborders, 

 or rather strongly marked tribes. 



Synopsis. 



TEIBE I. CONVOLVULE^:. Embryo with broad and foliaceous cotyledons crumpled 

 in the seed. Ovary 2 - 3- (or falsely 4-) celled. Pod usually septifragal Leafy plants. 



* Style 1. undivided. 

 H- Calyx naked, i. e. not enclosed or surrounded by bracts. 



1. QUAMOCLIT. Stamens exserted. Corolla cylindrical-tubular, with a spreading border. 



Stigma capitate-2-lobed. Pod 4-elled ; the cells 1-seeded. 



2. 1POMCEA. Stamens included. Corolla funnel-form or bell-shaped. Stigma capitate, of- 



ten 2 - 3-lobed. Pod 2 - 3-celled ; cells 2-seeded. 



8. CONVOLVULUS. Stigmas 2, elongated, linear. Otherwise much as in No. 2. 

 i- +- Calyx surrounded by 2 broad bracts. 



4. CALYSTEGIA. Stigmas 2, linear or oblong. Pod imperfectly 2-celled, 4-seeded. 



* * Style 2-cleft, or styles 2, rarely 3. 



5. STYLISMA. Styles or their divisions simple : stigma depressed-capitate. 



TRIBE II. DICHOIVDRE^K. Pistils 2, separate. Otherwise nearly as Tribe I. 



6. DICHONDRA. Corolla bell-shaped. Pods 2, each 1-seeded. 



TKIBE III. CUSCTJTINEJE. Embryo spiral, slender, destitute of cotyledons. Ovary 

 2-celled. Leafless parasitic twiners. 



7 CUSCUTA. The only genus of the group. 



1. <UAITIOCr,IT, Tourn. CYPRESS-VINE. 



Sepals mostly mucronate or awnecl. Corolla cylindrical-tubular, with a small 

 spreading border. Stamens and style protruded. Stigma capitate-2-lobed. 

 Pod 4-celled ; the cells 1-sceded. Annual twiners, with red or crimson flowers* 

 (An aboriginal, probably Mexican, name.) 



1. C. cocciNEA, Moench. Leaves heart-shaped, acuminate, entire, or 

 angled; sepals awn-pointed; corolla light scarlet (!' long). (Ipomoea coccinea, 

 L.) Elver-banks, c., Ohio, Virginia, and southward. (Nat. from Trop. 

 Amer. or Ind. ) 



Q. VULG\RIS, the cultivated CYPRESS-VINE, is becoming spontaneous iu 

 the South. 



2. IPOM4EA, L. MORNING-GLORY. 



Calyx naked at the base. Corolla bell-shaped, funnel-form, &c. Stamens 

 included. Stigma capitate, often 2 -3-lobed. Pod 2-cclled, or in one group 3- 

 celled ; the cells 2-seeded. (Name, ex L. from ity, ITTOS, a Bindweed [which it is 

 not], and opoios, like.) 



1 . PHARBITIS, Choisy. Pod 3- (rarely 4-) celled; the cells 2-seeded. 

 t. I. PURFtiREA, Lam. (COMMON MORNING-GLORY.) Stems rctrorsel/ 

 hairy : leaves heart-shaped, 'icuminat?- entire ; peduncles long umbellataly 3-5- 

 flowered ; calyx bristly-hai y below ; corolla funnel-form (2 long), purple vary 



