PHR YMA ChAE. 855 



Flowers capitate, the heads dense, at length oblong. 1. D. Americana. 

 Flowers in loose spikes. 



Flowers in pairs in the spikes. 2. D. ovata. 



Flowers scattered singly along the spikes. 3. D. lanceolata. 



1. Dianthera Americana L. Dense-flowered Water Willow. (I. F. f. 

 3374.) Perennial, glabrous; stem erect, angled, slender, usually simple, 3-9 dm. 

 high. Leaves lanceolate or linear-lanceolate, gradually acuminate, 7-15 cm. long, 

 entire, narrowed at the base into short petioles, or sessile; flowers violet, or nearly 

 white, capitate-spicate at the ends of slender axillary peduncles; bractlets linear- 

 subulate, shorter than the flowers; corolla 10-12 mm. long, its tube shorter than 

 the lips, the base of the lower lip rough and palate-like; capsule 12 mm. long, ex- 

 ceeding the calyx, its stipe about the length of the slightly compressed body. In 

 water and wet places, Ont. to Mich., Kans., Ga. and Tex. May-Aug. 



2. Dianthera ovata Walt. Loose-flowered Water Willow. (I. F. f. 

 3375.) Perennial, glabrous; stem ascending or erect from a horizontal base, 1.5-5 

 dm. high, simple, or sparingly branched. Leaves short-petioled, or sessile, ovate, 

 oblong, oval to elliptic-obovate, 2-8 cm. long, 8-35 mm. wide; flowers in loose 

 slender-peduncled axillary spikes; peduncles shorter than or little exceeding the 

 leaves; calyx-segments narrowly linear, much longer than the bracts and bractlets; 

 corolla pale purple, 8-10 mm. long; capsule 10-12 mm. long. In wet soil, Va. 

 to Fla. and Tex. June-Aug. 



3. Dianthera lanceolata (Chapm.) Small. Narrow-leaved Water Wil- 

 low. Perennial, often minutely puberulent: stems erect or spreading, 1-3 dm. 

 long~ Leaves linear to linear-elliptic or elliptic-lanceolate. 3-10 cm. long, often 

 acuminate, undulate, sessile, or nearly so; spikes slender, 3-10 cm. long, the 

 flowers scattered singly and quite evenly along one side of the peduncle; calyx- 

 segments narrowly linear. 5-7 mm. long: corolla about I cm. long, the lips nearly 

 as long as the tube, which is saccate at the base; capsules about 1.5 cm. long, the 

 body as long as the stipe-like base or shorter. In swampy grounds, Mo. to Tenn., 

 Fla. and Tex. May-Aug. (D. ovata var. lanceolata Chapm.) 



4. DIAPEDIUM Konig. [DICLIPTERA Juss.] 



Herbs, with entire petioled leaves, and blue, red. or violet flowers, subtended by 

 involucres of 2-4 bracts, the inflorescence mostly cymose or spicate, the involucres 

 subtending I flower or several. Calyx 4-5 -cleft, the lobes linear or subulate. 

 Corolla-tube slender, slightly enlarged above; upper lip erect, concave, interior in 

 the bud; lower lip spreading, entire or 3-toothed. Stamens 2; anther-sacs paral- 

 lel, sometimes unequal, separated by a narrow connective. Style filiform; ovules 

 2 in each cavity of the ovary. Capsule flattened, ovate or suborbicular, 2-4-seeded. 

 Placentae separating elastically from the walls of the capsule. Seeds compressed, 

 nearly orbicular. About 60 species, of warm and tropical regions. Besides the 

 following. 4 others occur in the southern U. S. 



I. Diapedium brachiatum (Pursh) Kuntze. Diapedium. (I. F. f. 3376.) 

 Annual (?), glabrate, or pubescent; stem slender, 6-grooved, erect, much branched, 

 3-6 dm. high. Leaves ovate, membranous, long-petioled, acuminate or acute, 

 7-15 cm. long; inflorescence paniculate, the involucres 1-4-flowered, each of 2 

 oblong or obovate, opposite bracts; corolla 1. 5-2. 5 cm. long, pink or purple, the 

 lips about as long as the slender tube; upper lip 2-3-toothed, the lower entire; 

 capsule oblong. 4-6 mm. high, a little longer than the involucre, the valves slightly 

 divergent in dehiscence, the placentae curving upward and remaining attached to 

 their summits. In moist thickets, Kans. and Ind. Terr, to Tex., Fla. and N. Car. 

 July-Oct. 



Family 15. PHRYMACEAE Schauer. 



Lop seed Faintly. 



An erect perennial herb with divaricate branches, opposite mem- 

 branous simple leaves, and small irregular purplish flowers, distant in 

 slender elongated spikes. Calyx cvlindric, 2-lipped ; upper lip 2-cleft, 

 the teeth setaceous ; lower lip much shorter, 3-toothed, the teeth subu- 



