88O FLORA. 



empty cavities as thick as or thicker than the beaked fertile one and separated 

 from each other by a broad shallow groove. In moist soil, N. Y. to Fla., Mich., 

 Mo. and Tex. May -July. 



4. Valerianella stenocarpa (Engehn.) Krok. NARROW-CELLED CORN 

 SALAD. (I. F. f. 3478.) Similar to the preceding. Fruit oblong-tetragonal, slight- 

 ly smaller, glabrous or sometimes pubescent; sterile cavities not as thick as the ob- 

 long seed-bearing one, and separated from each other by a narrow groove. Kans. 

 and Mo. to Tex. March-June. 



5. Valerianella Woodsiana (T. & G.) Walp. WOODS' CORN SALAD. 

 (I. F. f. 3479. ) Usually larger than any of the preceding species, sometimes 9 dm. 

 high, glabrous or nearly so. Basal and lower leaves spatulate, obtuse, entire; up- 

 per leaves lanceolate to linear-oblong, usually dentate; cymes 6-12 mm. broad, 

 few-flowered; bracts comparatively large, lanceolate; corolla white, about 2 mm. 

 long; fruit glabrous, nearly globular, about 2 mm. in diameter, the empty cavities 

 inflated, introrse with a depression or concavity between them, as broad as the 

 fertile one. In moist soil, N. Y., Penn. and Ohio to Tenn. and Tex. May-July. 



Valerianella Woodsiana umbilicata (Sulliv.) A. Gray. Empty cells of the fruit 

 bladdery-inflated, curved together at the ends, forming a deep concavity. Same range. 



Valerianella Woodsiana patellkria (Suliiv.) A. Gray. Empty cells divergent, the 

 fruit becoming saucer-shaped. Ohio and Penn. 



6. Valerianella longiflora (T. & G.) Walp. LONG-FLOWERED CORN SALAD. 

 (I. F. f. 3480.) Glabrous, 1.5-3 dm. high. Leaves very obtuse, the basal ones 

 spatulate, 2.5-7 cm. long, those of the stem oblong or spatulate-oblong, smaller, 

 somewhat clasping; cymes dense, corymbed; corolla salverform, pink or purplish, 

 about 12 mm. long, the almost filiform tube 3 -4 times as long as the limb, the lobes 

 linear-oblong; bracts with small gland-tipped teeth; fruit broadly ovate or nearly 

 orbicular, the empty cavities divergent, larger than the oblong seed-bearing one. 

 In moist rocky situations, Mo. and Ark. April -May. 



Family 2. DIPSACACEAE Lindl. 



Teasel Family. 



Herbs, with opposite or rarely verticillate leaves, and perfect flowers 

 in dense involucrate heads. Stipules none. Flowers borne on an elon- 

 gated or globose receptacle, bracted and invohicellate. Calyx-tube ad- 

 nate to the ovary, its limb cup-shaped, disk-shaped, or divided into 

 spreading bristles. Corolla epigynous, the limb 2-5-lobed. Stamens 

 2-4, inserted on the tube of the corolla and alternate with its lobes; fila- 

 ments distinct ; anthers versatile. Ovary inferior, i-celled ; style filiform ; 

 stigma undivided, terminal, or oblique and lateral ; ovule i, anatropous. 

 Fruit an achene, its apex crowned with the persistent calyx-lobes. Seed- 

 coat membranous ; endosperm fleshy ; embryo straight. About 7 genera 

 and 140 species, of the Old World. 



Scales of the elongated receptacle prickly pointed. I. Dipsacus 



Scales of the receptacle not prickly, herbaceous, capillary, or none. 2. Scabiosa. 



i. DI'PSACUS L. 



Rough-hairy or prickly tall biennial or perennial herbs, with usually large 

 leaves, and blue or lilac flowers in dense terminal peduncled oblong heads in our 

 species. Bracts of the involucre and scales of the receptacle rigid or spiny point- 

 ed. Involucels 4-8-ribbed, with a somewhat spreading border. Limb of the calyx 

 cup-shaped, 4-toothed or 4-lobed. Corolla oblique or 2-lipped, 4-lobed. Stamens 

 4. Stigma oblique or lateral. [Greek, to thirst, the leaves of some species hold- 

 ing water.] About 15 species, of the Old World. 



Scales of the receptacle straight-pointed. i. D. sylvestris. 



Scales of the receptacle hooked at the apex. 2. D. fitllonum. 



I. Dipsacus sylvestris Huds. WILD TEASEL. (I. F. f. 3481.) Biennial, 

 stout, with numerous prickles, otherwise glabrous or nearly so, 1-2 m. high. 

 Leaves sessile, or the upper connate-perfoliate, lanceolate or oblong, the upper 

 acuminate and generally entire, the lower crenate or sometimes pinnatifid, often 

 3 dm. long; heads becoming cylindric, at length 7-10 cm. long; flowers lilac, 



