This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", 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..
Herbs with stipulate palmately lobed, cleft or parted leaves, and axillary 1-2-flowered peduncles. Flowers regular, 5-merous. Sepals 5, imbricated. Petals 5, hypogynous, imbricated. Stamens 10 (rarely 5), generally 5 longer and 5 shorter. Ovary 5-lobed, 5-celled, beaked with the compound style. Ovules 2 in each cavity. Capsule elastically dehiscent, the 5 cavities I-seeded, long-tailed. [Greek, a crane, from the long beak of the fruit.]
About 190 species, widely distributed in temperate regions. Besides the following, some 60 others occur in North America. Type species: Geranium sylvąticum L.
Perennial; flowers 1' broad or more.
Beak of the fruit, and pedicels, glandular-pubescent.
Beak of the fruit, and pedicels, pubescent, but not glandular.
Annuals or biennials; flowers 2"-6" broad.
Peduncles longer than the leaves; carpels smooth and glabrous.
Peduncles short; carpels rugose or hairy.
Seeds reticulated or pitted.
Glandular-pubescent with long white hairs.
Pubescent with short hairs; leaves deeply lobed.
Flowers pale purple; seeds minutely reticulated.
Beak short-pointed; inflorescence compact.
Beak long-pointed; inflorescence loose.
Flowers deep purple; seeds deeply pitted.
Seeds smooth or nearly so.
Stamens 5; carpels hairy, not rugose.
Stamens 10: carpels glabrate, rugose.
Geranium pratense L. Sp. Pl. 681. 1753.
Perennial by a stout rootstock. pubescent with spreading or retrorse short hairs, erect, 1°-2 1/2° high. Basal leaves long-petioled, reni-form or orbicular-reniform in outline and decidedly pentagonal, mostly 4'-5' wide, 5-7-parted, the divisions narrower, more attenuate and more finely cut than in G. maculatum; stem-leaves usually with narrower divisions and teeth than the basal leaves; peduncles elongated, glandular-pubescent like the pedicels which are very variable in length; flowers deep-purple, 1 1/4'-1 3/4' broad; petals ciliate at the base; beak of the fruit 3/4'-1' long; carpels minutely pubescent; seeds reticulate.
Geranium pyrenąicum L., of Europe, a perennial with much smaller flowers, the sepals obtusish, has been found in waste places in Quebec and Pennsylvania.