1903.] NATURAL SCIENCES OF PHILADELPHIA. 665 



I, Acaulescent Species. 



I. — Plants producing stolons after the flowering season. 



a. — Flowers yellow, V. rotundifolia. 



aa. — Flowers white. 



b. — Leaves cordate at base, cleistogenes on horizontal pe- 

 duncles. 

 c. — Petioles and scapes spotted with red, V. Uconteano. 

 cc. — Petioles and scapes unspotted, . . . V. blanda. 

 bh. — Leaves decurrent on the petiole, cleistogenes erect. 



c. — Leaves oval, V. ovata. 



cc. — Leaves lanceolate, V. lanceolata. 



II. — Plants not stoloniferous, flowers blue. 

 a. — Leaves more or less lobed or cut. 

 b. — Leaves and petioles pubescent. 



c. — Lobes not deeply cut, only about half-way to the base, 



V. palviato. 

 cc. — Lobes deeply cut, nearly to the base, 



V. p. dilatata, variabilis and angellcc. 

 bb. — Leaves and petioles nearly or quite glabrous. 

 c. — Middle lobe undivided, no cleistogenes, 



V. pedata and subsp. 

 cc. — Middle lobe divided in three, cleistogenes present. 

 d. — Leaves large; lobes broad, much narrowed at 



base, V. septemloba . 



dd. — Leaves medium, lobes nearly linear, 



V. brittoniana. 

 aa. — Leaves not lobed, never coarsely toothed or sagittate at the 

 base. 

 b. — Leaves strongly hispid-pubescent above, glabrous below 



and on petiole, V. villosa cordifolia, 



bb. — Leaves pubescent, on blade and petiole, 



cf. V. palmata dilatata and V. fimbriatula aberrans. 

 bbb. — Leaves glabrous or very nearly so. 

 c. — Cleistogenes on erect pedicels. 



d. — Leaves cordate-ovate, plants medium or large, 



V. cucullata and subsp. 

 dd. — Leaves nearly triangular, plants small, 



V. crenulala. 

 cc. — Cleistogenes deflexed or horizontal. 



d. — Leaves broadly cordate or reniform, apex not 

 produced, flowers deep purple, 



V. papilionacea. 

 dd. — Leaves more triangular, apex attenuate, flowers 



pale lilac, V. affinis. 



aaa. — Leaves sagittate, triangular or oval, usually with several 

 coarse teeth at the base. 

 Leaves sagittate, usually glabrous, . . . . V. sagiitata. 

 Leaves oval, or with truncate base, strongly pubescent, 



V. fimbriatula. 

 Leaves triangular, thick, fleshy, glabrous. . V. emarginata 



