PLAXTAIN FAMILY 225 



3-lobed. Stamens 2, inserted in the throat of the corolla. 

 Ovary 2-celled, 4-ovuled ; style simple, acute. Capsule flat- 

 tened, narrowed below into a little stalk.* 



1. D. americana L. '\^^ATER "Wij.low. Stem erect, slender, 2-3 ft. 

 high. Leaves lanceolate to linear-lanceolate, taper-pointed at the 

 apex, narrowed below to the sessile or short-petioled base. Flowers 

 bracted, in short spikes, on peduncles as long as the leaves. Corolla 

 pale blue or purple, the tube as long as the lips, lower lip wrinkled. 

 Capsule about the length of the calyx. In water, S.* 



n. RUELLIA L. 



Perennial herbs ; stems swollen at the joints and often 

 between them, somewhat 4^angled. Leaves sessile or short- 

 petioled, mostly entire. Flowers axillary, solitary or clustered, 

 showy, white, blue, or purple. Calyx 2-bracted, 5-parted, the 

 divisions linear and awl-shaped. Corolla tube slender, often 

 much elongated, the limb spreading, nearly equally 5-lobed. 

 Stamens 4 (2 long and 2 short), included or slightly projecting. 

 Style slender. Capsule slender, narrowed below, 4-12-seeded.* 



1. R. ciliosa Pursh. Hairy Ruellia. Stem erect, rather stout, 

 often few-branched above, covered with white hairs, 4-30 in. high. 

 Leaves oblong to ovate, acute or obtuse at the apex, narrowed and 

 mostly sessile at the base, hairy-fringed. Flowers pale blue, solitary 

 or 2-3 together. Calyx lobes bristle-shaped, half the length of the 

 corolla tube. Tube of the corolla 2 in. long. Capsule shorter than 

 the calyx, smooth, 8-12-seeded. A very variable species, the flowers 

 often without a corolla. In dry woods and fields S.* 



2. R. strepens L. Smooth Kuellia. Stem erect, slender, usually 

 simple, smooth or hairy, 1-8 ft. high. Leaves ovate to oblong, acute 

 at the apex, narrowed below into a short petiole. Flowers solitary or 

 in small clusters, sessile or short-peduncled. Calyx lobes shorter than 

 the tube of the corolla, downy oi^f ringed. Corolla blue, the tube 1 J-2 

 in. long, the limb 1-1^ in. wide. Capsule usually longer than the 

 calyx, smooth, 8-12-seeded. The later flowers often without a corolla. 

 On rich, dry soil.* 



94. PLANT AGINACEiE. Plaxtaix Faiiily 



Annual or perennial scape-bearing herbs. Leaves usually 

 all basal, with parallel ribs. Flowers small, green, usually 



