742 ACANTHACEAE (ACANTHUS FAMILY) 



imperfectly 6-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 

 Martyn, of Cambridge, England.) 



1 . M. louisiana Mill. Leaves 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. proboscidea 

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

 cultivated and naturalized northw. 



ACANTHACEAE (ACANTHUS FAMILY) 



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

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

 convolute or imbricated in the bud' fruit a 2-celled and few (4-12) -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. 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. 

 8. 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 &v6tjpA., anther, the separated 

 cells giving the appearance of two anth'ers 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, 1.6-4 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 rin^s 

 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 Ruelle.) 



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

 in-iirhj sr.s.s'/Vr, nrnl or ovate-oblong, 2.5-7 cm. long; flowers 1-3 and almost 

 in the axils; tube of the corolla 2.6-4 cm. long, fully twice the length of 



