742 ACANTHACEAE (ACANTHUS FAMILY) 



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

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

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

 MarUjn, of Cambridge, England.) 



1. M. louisislna Mill. Leaves heart-shaped, oblique, entire or undulate, the 

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

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

 Gloxin.) — River-banks and waste places, s. Ind., 111., and la. to n. Mex. ; also 

 cultivated and naturalized north w. 



ACANTHACEAE (Acanthus Family) 



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

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

 concolute or imbricated in the bud; fruit a 2-ceUed and few (^i-\2) -seeded 

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

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

 bracted. Calyx 5-cleft. Style thread-form ; S'tigma simple or 2-cleft. Pod 

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

 broad and flat. — Mucilaginous and slightly bitter, not noxious. A large family 

 in the 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. 



3. Dyschoriste. Calyx-lobes long-filiform. Capsule 2-4-seeded. 



1. DIANTHERA [Gronov.] L. Water Willow 



Calyx 5-parted. Upper lip of corolla notched ; the lower spreading, 3-parted, 

 external in the bud. Anthers 2-celled, 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 dls, double, and dvdripd, anther, the separated 

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



1. D. americana 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.) 



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

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

 sessile in the axils; tube of the corolla 2.5-4 cm. long, fully twice the length of 



