218 ELEMENTS OF BOTANY. 



divisions linear and subulate ; corolla tube slender, often 

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

 stamens 4, didynamous, included or slightly exserted; style 

 slender ; capsule slender, narrowed below, 4-12-seeded. 



1. R. strepp:ns L. Smooth Kuellia. Stem erect, slender, 

 usually simple, smooth or hairy, 1-3 ft. high ; leaves ovate to oblong, 

 acute at the apex, narrowed below into a short petiole ; flowers soli- 

 tary or in small clusters, sessile or short-peduncled ; calyx lobes 

 shorter than the tube of the corolla, pubescent or ciliate ; corolla 

 blue, the tube lj-'2 in. long, the limb 1-1 j in. wide; capsule usually 

 longer than the calyx, smooth, 8-12-seeded ; the later flowers often 

 without a corolla. May-September. On rich, dry soil. 



2. E,. ciLiosA Pursh. Haiky Ruellia. Stem erect, rather 

 stout, often few-branched above, hirsute with w^hite hairs, 4-30 in. 

 high ; leaves oblong to ovate, acute or obtuse at the apex, narrowed 

 and mostly sessile at the base, ciliate ; flowers pale blue, solitary or 

 2-3 together ; calyx lobes setaceous, 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 with- 

 out a corolla. June-September. In dry woods and fields. 



II. DIANTHERA. 



Perennial herbs ; stem smooth ; leaves opposite, entire or 

 dentate ; flowers axillary, solitary or clustered, irregular ; 

 calyx 5-parted ; corolla bilabiate, upper lip erect, concave, 

 entire or emarginate, the lower prominently veined, spread- 

 ing, 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 stipe. 



1. D. Americana L, Water AVillow. Stem erect, slender, 

 2-3 ft. high ; leaves lanceolate to linear-lanceolate, acuminate 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 rugose ; 

 capsule about the length of the calyx. May-August. In water. 



2. ]). ovATA Walt. Loosp>FLOWERED Water Willow. Stcms 

 erect or ascending from a creeping base, slender, simple, 4-12 in. 

 high ; leaves ovate to lanceolate, sessile or short-petioled ; spikes 

 few-flowered, on peduncles shorter than the leaves; calyx lobes subu- 

 late ; corolla less than i in. long, pale purple, the lower lip with 

 darker veins ; capsule longer than the calyx. INIay-August. On 

 muddy banks. 



