742 ACANTHACEAE (; ACANTHUS FAMILY) 



imperfectly 5-oelled. Seeds several, with a thick roughened coat. — Low 

 branching annuals, clammy-pubescent, exhaling a heavy odor ; stems thickish ; 

 leaves simple, rounded ; flovrers racemed, large. (Dedicated to Prof. John 

 Martyn, of Cambridge, England.) 



1. M. louisijlna Mill. JLeaves heart-shaped, oblique, entire or undulate, the 

 upper alternate ; corolla dull white or purplish, or spotted with yellow and 

 purple ; endocarp of the fruit crested on one side, long-beaked. {M. prohoscidea 

 Gloxin.) — River-banks and waste places, s. Ind., Ill, and la. to n. Mex. ; also 

 cultivated and naturalized northw. 



ACANTHAcEAE (Acanthus Family) 



Chiefly herbs, with opposite simple leaves, didyrtamous or diandrous stamens 

 inserted on the tube of the more or less 2-lipped corolla, the lobes of which are 

 eonoolute or imbricated in the bud; fruit a 2-celled and few (i-l^) -seeded 

 capsule; seeds anatropous, without albumen, usually flat and supported by 

 hooked projections of the placentae (retinacula). Flowers commonly much 

 bracted. Calyx 5-cleft. Style thread-form ; stigma simple or 2-cleft. Pod 

 loculicidal, usually flattened contrary to the valves and partition. Cotyledons 

 broad and flat. — Muoilagino'is and slightly bitter, not noxious. A large family 

 in t\e warmer parts of the world ; represented in gardens by Thunbergia, 

 which differs from the rest by the globular pod and seeds, the latter not on 

 hooks. 



* Corolla bilabiate, upper lip erect and concave, lower spreading ; stamens 2. 



1. Dianthera. Capsule obovate, flattened, 4-seeded. 



* * Corolla not obviously bilabiate, the 5 lobes broad and roundish, spreading ; stamens 4. 



2. Ruellia. Calyx-lobes mostly linear or lanceolate. Capsule 6-20-seeded. 

 8. Dysohoriste. Calyx-lobes long-flliform. Capsule 2-4-seeded. 



1. DIANTHERA [Gronov.] L. Water Willow 



Calyx 5-parted. Upper lip of corolla notched ; the lower spreading, S-parted, 

 external in the bud. Anthers 2-oelled, the cells separated and somewhat unequal. 

 Capsule contracted at base into a short stalk. — Perennial herbs, growing in 

 water or wet places, with entire leaves, and purplish flowers in axillary peduncled 

 spikes or heads. (Name formed of Sh, double, and ivB-qpi, anther, the separated 

 cells giving the appearance of two antliers on each filament.) 



1. D. americina L. Stem 3-9 dm. high ; leaves linear-lanceolate, elongated ; 

 spikes cylindric, dense, long-peduncled ; corolla 1 cm. long, the lower lip 

 rugose. — In water, w. Que. and Vt. to Wise, s. to Ga. and Tex. July-Sept. 



2. D. ovata Walt. Slender, 1.5-4 dm. high ; leaves oblong or ovate-oblong ; 

 peduncles mostly shorter than the leaves. — Swamps, etc., Va. to Fla. and Tex., 

 inland to Mo. 



2. RUELLIA [Plumier] L. 



Calyx 5-parted. Corolla funnel-form, with spreading ample border, convo- 

 lute in bud. Cells of the somewhat arrow-shaped anthers parallel and nearly 

 equal. Capsule narrow, in ours somewhat flattened, contracted and seedless 

 at base. Seeds with a mucilaginous coat, when wet exhibiting under the 

 microscope innumerable tapering short bristles, their walls marked with rings 

 or spirals. — Perennials, with large showy blue or purple flowers, sometimes 

 also with small flowers precociously close-fertilized in the bud. Calyx often 

 2-bracteolate. (Named for the early French herbalist, Jean Buelle.) 



! R. cilibsa Pursh. Hirsute with soft whitish hairs, 3-9 dm. high ; leaves 

 TiSa.-lt, sessile, oval or ovate-oblong, 2.5-7 cm. long; flowers 1-3 and almost 

 sessile in the axils; tube of the corolla :^.S-4 cm. long, fully twice the length of 



