LOBELIA FAMILY 827 



5. L. strictiflora (Rydb.) Lunell. Biennial; stem slender, glabrous or 

 puberulent at the base, 1-3 dm. high, simple or with a few erect branches; basal 

 leaves petioled; blades spatulate or oblanceolate, puberulent or glabrate; pedicels 

 erect, 5-8 mm. long, usually glabrous, sometimes glandular-pilose; hypanthium 

 turbinate, 2-3 mm. long; sepals subulate, 3 mm. long; corolla 7-8 mm. long. L. 

 Kalmii strictiflora Rydb. Meadows and bogs: Man. N.D. Mont. Wash. 

 B.C. Submont. Jl-Au. 



6. L. Dortmanna L. Acaulescent perennial; leaves all basal, tufted, linear, 

 fleshy, terete, fistulose, with two longitudinal tubes, 1-5 cm. long; scape 1-4 dm. 

 high, simple; hypanthium turbinate, in fruit clavate; sepals lanceolate, 2-3 mm. 

 long; corolla blue, 12-15 mm. long. In water: Lab. N.J. Wash. B.C.; Eu. 

 Subarctic. Jl-Au. 



FAMILY 132. DIPSACEAE. TEASEL FAMILY. 



Herbs, with opposite or rarely whorled leaves. Flowers perfect, in invo- 

 lucrate heads, each usually with an involucel. Calyx cup-like or of several 

 bristles. Corolla gamopetalous, tubular-funnelform, with 2-5-lobed limb. 

 Stamens 2-4, adnate to the upper part of the corolla-tube; filaments distinct; 

 anthers versatile, opening lengthwise. Gynoecium of a single carpel; ovary 

 inferior, 1-celled; style elongate, entire; stigma globose to elongate. Fruit 

 an aohene; embryo straight; endosperm fleshy. 



1. DIPSACUS L. TEASEL. 



Coarse herbs. Leaves opposite, coarsely toothed or pinnatifid. Involucral 

 bracts and paleae of the receptacle rigid. Involucel calyx-like, enclosing the 

 ovary. Calyx cup-shaped or 4-lobed. Corolla 4-lobed, slightly irregular, blue 

 or white. Stamens 4. Achenes 8-ribbed. 



1. D. sylvestris Huds. Coarse biennial herb, armed with stout prickles; 

 stem 1-2.5 m. high; basal leaves oblanceolate, crenate-serrate, 2-4 dm. long; stem- 

 leaves lanceolate, entire, sparingly spiny on the margins, clasping; heads ovoid, 

 5-6 cm. long; bracts linear-lanceolate; paleae with a long straight spine-point; 

 corolla 10-13 mm. long, white, with lilac lobes. Waste places and fields: Me. 

 Va. Mich.; Colo. Utah; adv. or nat. from Eu. Jl-S. 



FAMILY 133. AMBROSIACEAE. RAGWEED FAMILY. 



Annual or perennial herbs, rarely shrubs, monoecious or dioecious. Leaves 

 alternate, or opposite on the lower part of the stem. Flowers in small heads, 

 the staminate and pistillate ones in the same head or in different heads. 

 Involucral bracts few, distinct or more or less united. Pistillate flowers, 

 when in distinct heads usually enclosed in a bur-like or nut-like involucre. 

 Staminate flowers with tubular, obconic, or funnelform corollas, 4-5-lobed; 

 pistillate flowers corolla-less or with a small border or crown. Calyx none 

 or rudimentary. Ovary inferior. Stamens 5, distinct. Stigmas 2, hairy 

 at the top. Ovules and seeds solitary. 



Staminate and pistillate flowers in the same heads, the latter few (rarely solitary or none) , 



marginal. 

 Achenes turgid, oboyoid or pear-shaped, marginless. 



Involucres of 5 dilated-ovate, rigidly acuminate bracts; achenes with a large ter- 

 minal areola, surrounded by a disk. 1. OXYTENIA. 

 Involucres not with dilated rigidly acuminate bracts; terminal areola minute. 

 Heads paniculate; corolla of the pistillate flowers rudimentary or none. 



2. CYCLACHAENA. 



Heads spicately or racemosely disposed; corolla of the pistillate flowers evi- 

 dent. 3. IVA. 



Achenes flattened, wing-margined; involucres of 5 ovate or oblong herbaceous bracts 

 and within them 1-2 large scarious ones subtending the pistillate flowers. 



4. DICORIA. 



