This section is from the book "Sub-Alpine Plants Or Flowers Of The Swiss Woods And Meadows", by H. Stuart Thompson. Also available from Amazon: Sub-Alpine Plants: Or, Flowers of the Swiss Woods and Meadows.
Annual or biennial. Corolla 4-lobed, lilac, but frequently darker violet and sometimes white. (Plate XXV.) Calyx-teeth very unequal, the two outer lobes three times as broad as the inner ones, the former being ovate-acuminate, and the latter lanceolate.
Rather dry places in the Alps, sub-Alps, and hills. It ascends to 9300 feet in Switzerland, as, e.g. on the Col de Torrent. May to August.
Central and Northern (but, excepting Iceland, not Arctic) Europe, and most of the mountain ranges in the south; Spain, Italy. British.
This little-understood plant is probably a sub-species of the last. Dr. C. E. Moss tells me he considers the English lowland form of "G. campestris," which is usually biennial, to be the annual G. baltica. Stem erect, often branched above, usually still bearing the cotyledons at time of flowering; they are broadly lanceolate. Upper leaves sessile-acute. Calyx-lobes as in campestris. Corolla 4-lobed, violet or white. Capsule sessile, cylindric, finally longer than the corolla.
In Switzerland it has been recorded from Schafberg and near Samaden in Grisons and from Villeneuve in Valais. In England the true plant grows in several places as, e.g. on the Lancashire sand-hills.
An erect, much-branched annual, 3-10 inches high; often purplish or livid green in colour. Leaves ovate or lanceolate. Flowers numerous, usually crowded in a leafy panicle, pale purplish blue. Corolla-lobes 5, ovate or oblong, spreading, with a fringe of hairs at the mouth of the broad tube. Calyx divided to the middle into 5 narrow lobes.
Europe, especially Central and Northern, extending to the Arctic Circle in both Europe (Iceland) and Asia. Rare in Switzerland (Lower Engadine), Roumania. British.
Larger and stouter than G. Amarella, but also frequently purplish in colour, the stems and leaves being sometimes a distinct reddish purple. An annual, about 10-18 inches high. Stem-leaves ovate or ovate-lanceolate. Calyx-lobes unequal, shorter than corolla-tube, usually glabrous, but sometimes finely ciliate, lanceolate. Corolla large, 4-lobed, deep lilac or violet, campanulate.
Pastures, open woods, etc., in the plains, hills, and Alpine valleys; preferably on limestone, August to October.
Central Europe, extending to Northern France, Holland, Belgium, Germany, and Southern England. In Switzerland in the central plateau and such Alpine localities as Andermatt and St. Moritz. N. Italy, Servia, Roumania, Russia.
A more Alpine form of G. germanica is called G. rhcetica Kerner. The corolla-lobes are never spreading, the stems are shorter and the stem-leaves rather longer. It has been recorded from the Albula in Eastern Switzerland. It apparently prefers siliceous soil.
Biennial or perennial. Stem 3-10 inches high, simple or branched, leafy to the top. Leaves erect, lanceolate or linear-lanceolate, acute, 1-nerved. Flowers rather pale blue, large and handsome, solitary or several on a stem. Corolla divided to the middle into 4 spreading lobes, which are toothed and strongly ciliated. Calyx campanulate, with 4 lanceolate, acuminate segments, much shorter, than the long tube. The blue may be called electric.
Pastures and sloping banks in the Alps, sub-Alps, and plains, especially on shale or limestone. August to October. The writer has found it from 8250 feet on the Aiguille de Goleon in Dauphiny, and from near Annecy at only 1650 feet. It is distinctly an autumnal species.
Central and Southern Europe, from Belgium to Bulgaria; Spain, Pyrenees, Italy, Alps, S. Russia, Cilicia, Armenia, Caucasus.