This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol3", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Perennial or annual herbs, with alternate or basal leaves. Flowers large or small, solitary, racemose, paniculate, or glomerate, regular, complete, blue, violet, or white. Calyx-tube hemispheric, turbinate, obovoid, or prismatic, adnate to the ovary, the limb deeply 5-lobed or 5-parted (rarely 3-4-parted). Corolla campanulate or rotate, 5-lobed or 5-parted. Stamens 5, free from the corolla; filaments usually dilated at the base; anthers separate. Ovary inferior, 3-5-celled; stigma 3-5-lobed. Capsule wholly or partly inferior, crowned by the persistent calyx-lobes, opening on the sides, either near the top, middle or bottom by 3-5 small valves or perforations, or tending to be indehiscent in some species. [Diminutive of the Latin campana, a bell.]
About 250 species, natives of the northern hemisphere. Besides the following, some 8 others occur in the southern and western parts of North America; all known as Bell-flower. Type species: Campanula latifolia L.
*Corolla campanulate; flowers solitary, racemose, glomerate, or panicled.
Flower solitary at the end of the stem; arctic and alpine plants. Corolla 4"-6" long; capsule-openings near the summit.
1. C. uniflora.
Corolla 6"-12" long; capsule-openings near the base.
2. C. rotundifolia.
Flowers racemose, glomerate, or paniculate. Corolla 7"-15" long.
Stem leaves linear, the basal orbicular, mostly cordate.
2. C. rotundifolia.
Leaves all ovate to lanceolate; plants pubescent or scabrous. Flowers pedicelled, or clustered.
Calyx and corolla glabrous, or calyx finely pubescent.
3. C. rapunculoides.
Calyx and corolla bristly-hairy.
4. C. Trachehuni.
Flowers sessile in terminal and axillary clusters.
5. C. glomerata.
Corolla 2-5 long.
Plants rough; style not exserted.
Corolla white, or tinged with blue, 21/2"- 4" long; leaves mostly linear-lanceolate, crenulate.
6. C. aparinoides.
Corolla blue, 5"-6" long; leaves linear, denticulate with minute callous teeth.
7. C. uliginosa.
Plants smooth, glabrous, slightly viscid; style long-exserted.
8. C. divaricata.
** Corolla rotate; flowers spicate.
9. C. americana.

Fig. 4015
Campanula uniflora L. Sp. Pl. 163. 1753.
Perennial, glabrous or nearly so; stem simple, 1-flow-ered, 1'-6' high. Leaves linear or linear-oblong, acute, sessile, thickish, entire or sparingly dentate, 9'-18" long, or the lower and basal ones spatulate, obtuse and narrowed into petioles; flower erect; calyx-tube turbinate, glabrous or pubescent, shorter than or equalling the lobes; corolla campanulate, 4"-6" long, blue; capsule cylindric or club-shaped, about 6" long, erect, opening by valves near the summit.
Labrador and Arctic America to Alaska, south in the Rocky Mountains to Colorado. Also in northern Europe and Asia. Summer.
 
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