ACANTHACE.E. (ACANTHUS FAMILY.) 303 



Nfv 2. DIPTERACANTHUS, Nees. 



Calyx 2-bracted, 5-parted, with linear or bristle-like lobes. Corolla funnel- 

 shaped, 5-lobed; the lobes equal, rounded. Stamens 4, didynamous, included : 

 anthers sagittate. Style simple, or 2-cleft at the apex. Capsule narrowed 

 below the middle, flattened contrary to the partition, 4 - 12-seeded. Seeds borne 

 above the middle, supported by curved appendages of the placentas. Perennial 

 herbs, with tumid joints, entire opposite leaves, and axillary solitary or clustered 

 nearly sessile flowers. Corolla white, blue, or purple. 



1. CALOPHANES. Anther-cells pointed at the base: style simple: capsule 



i-seeded. 



1. D. Oblongifolius. Pubescent and somewhat hoary; stem 4-angled, 

 erect from a creeping base, simple or sparingly branched ; leaves nearly sessile, 

 oval or obovate, obtuse, the upper ones narrower and often acute ; flowers soli- 

 tary or 2 - 3 in a cluster ; calyx-lobes subulate-setaceous, as long as the oblong 

 bracts, and tube of the spotted purple corolla. (Ruellia oblongifolia, Michx.) 

 Dry sandy pine barrens, Florida to South Carolina, and westward. June- 

 August. Stem 6' -12' high. Leaves '-!' long. Corolla 1' long, rather 

 exceeding the leaves. 



2. D. riparius, n. sp. Stem minutely pubescent, erect from a creeping 

 base, simple, slender ; leaves smooth, membranaceous, oblong, obtuse, slightly 

 crenate, tapering into a long and slender petiole ; flowers clustered, sessile ; 

 calyx-lobes subulate-setaceous, shorter than the spatulate-oblong bracts ; corolla 

 white, 3-4 times shorter than the leaves. Shady banks of Little River, Middle 

 Florida. June and July. Stems l-l high. Leaves !'-!' long. Co- 

 rolla ' long. 



3. D. humistratus. Stem smooth, diffuse, creeping ; leaves oblong-oval, 

 entire, narrowed into a petiole ; flowers nearly sessile, solitary or 2 - 3 in a clus- 

 ter ; bracts oblong-spatulate, shorter than the setaceous calyx-lobes ; capsule 

 lanceolate, smooth. (Ruellia humistrata, Mchx.) Grassy places, Florida to 

 South Carolina. Plant small. Leaves ' long. 



4. D. linearis, Torr. & Gray. Small, rough-pubescent; stem prostrate, 

 diffuse, very leafy ; leaves oblong-linear, entire, narrowed toward the base, ob- 

 tuse ; calyx-lobes setaceous, hairy ; bracts similar to the leaves ; capsule oblong, 

 4-angled, at length 4-valved, 2 - 4-seeded. South Florida. Stem 6' long. 

 Leaves 4" -6" long. 



$ 2. DIPTERACANTHUS. Anther-cells pointless : style 2-clejt at the apex : capsule 



8 -12-seeded. 



5. D. ciliosus, Nees. Hirsute with white hairs ; leaves oval or ovate- 

 oblong, nearly sessile ; flowers solitary or 2-3 in a cluster; tube of the corolla 

 twice as long as the setaceous calyx-lobes, and much longer than the short 

 funnel-shaped throat; capsule smooth. (Ruellia ciliosa and R. hybrida, Pursli.) 

 Dry soil, Georgia, near Savannah, Pursh., and westward. July and Aug. 

 Stem varying from a few inches to 3 high. Leaves l'-2' long. Corolla 2' 

 long, pale blue. 



