ACANTHACEAE. 853 



the exocarp somewhat fleshy, the endocarp fibrous, woody, crested below or also 

 above, 4-celled by the extension of the placentae. Seeds numerous, tuberculate. 

 [Named for John Martyn, 1693-1768, professor of botany at Cambridge, England.] 

 About 8 species, natives of America. Besides the following, 2 others occur in the 

 southwestern U. S. 



1. Martynia Louisiana Mill. Unicorn-plant. Elephant's Trunk. Dou- 

 ble claw. (I. F. f. 3369.) Annual; stem stout, the branches prostrate or ascend, 

 ing, 3-10 dm. long. Leaves broadly ovate to orbicular, rounded at the apex, 

 cordate at the base, repand, undulate or entire, 0.7-3 dm. * n diameter, the petiole 

 stout; calyx somewhat cleft on the lower side; racemes several-flowered; pedicels 

 slender; corolla whitish or yellowish, mottled with purple or yellow within, 3-5 cm. 

 long, the lobes obtuse; fruit curved, 1-1.5 dm. long, the beak longer than the 

 body, splitting into 2 elastically diverging segments, the endocarp crested on the 

 under side. In waste places, escaped from gardens, Me. to N. J. and N. Car. 

 Native from Iowa, 111. and Kans. southward. July-Sept. ^M. proboscidea Glox. j 



Family 14. ACANTHACEAE J. St. HU. 



Acanthus Family. 



Herbs, or some tropical genera shrubs or small trees, with opposite 

 simple exstipulate leaves, and irregular or nearly regular perfect flowers. 

 Calyx inferior, persistent, 4-5-parted or 4-5-cleft, the sepals or segments 

 imbricated. Corolla gamopetalous, nearly regularly 5-lobed, or 2-lipped. 

 Anther-bearing stamens 4, didynamous, or 2 only; anther-sacs longitu- 

 dinally dehiscent. Disk annular, or cup-like. Ovary 2-celled ; ovules 2-10 

 in each cavity, anatropous or amphitropous ; style filiform, simple ; 

 stigmas 1 or 2. Capsule dry, 2-celled, loculicidally elastically 2-valved. 

 Seeds not winged, borne on curved projections (retinacula) from the 

 placentae, the testa close, mostly roughened, often developing spiral 

 threads and mucilage when wetted. Endosperm in the following genera 

 none; cotyledons flat, commonly cordate. About 175 genera and 1800 

 species, natives of temperate and tropical regions. 



Coron a convolute in the bud, nearly regular ; stamens 4. 



Ovules 2 in each cavity ; capsule 2-4-seeded. 1. Cahphanes. 



Ovules 3-10 in each cavity; capsule 6-20-seeded. 2. Ruellia. 

 Corolla imbricated in the bud, strongly 2-lipped: stamens 2. 



Lower lip of the corolla 3-cleft; flowers bracted, not involucrate. 3. Dianthera. 



Lower lip of the corolla entire or 3-toothed; flowers involucrate. 4. Diapedinm. 



I. CALOPHANES D. Don. 



Perennial herbs or shrubs, with entire leaves (smaller ones sometimes fascicled 

 in their axils), and blue or purple, rather large, axillary bracted flowers. Calyx 

 deeply 5 -cleft, the lobes setaceous. Corolla funnelform, the tube slightly curved, 

 the limb spreading, 5-lobed, somewhat 2-lipped, the lobes rounded. Stamens in- 

 cluded; anther-sacs mucronate at the base. Summit of the style recurved; stigma 

 simple, or of 2 unequal lobes. Capsule oblong, linear, narrowed at the base. 

 Seeds flat, orbicular, attached by their edges to the retinacula. [Greek, beautiful 

 appearance.] About 30 species, of wide distribution. Besides the following, 4 

 others occur in the southern U. S. 



1. Calophanes oblongifolia (Michx.)D. Don. Calophanes. (I. F. f. 3370.) 

 Rootstocks horizontal, slender. Stems slender below, pubescent or puberulent, ob- 

 tusely 4-angled, 1.5-4 dm. high. Leaves ascending or erect, oblong or oval, 

 rounded at the apex, short-petioled, or sessile, 1.5— 3 cm. long; flowers commonly 

 solitary in the axils; calyx-segment? filiform, hirsute, exceeding the oblong obtuse 

 bractlets; corolla blue, or mottled with purple. 1.5-2.5 cm. long, its tube enlarged 

 above; capsule oblong, about one-half the length of the calyx; anther-sacs mucronate- 

 aristate at the base. In sandy pine barrens, Va. to Fla. June-Sept 



