Herbs or shrubs, with alternate or opposite leaves; petals and sepals each 5, or the petals none; stamens 5 or 10; styles or stigmas 2-4.
| 1a. Shrubs with lobed leaves (3-15 dm. high; flowers in late spring)
[— 2.] | |
| 1b. Herbs [— 12.] | |
| 2a. Stems thorny [— 3.] | |
| 2b. Stems not thorny (Currant) [— 8.] | |
| 3a. Flowers and fruits in racemes | Swamp Currant, Ribes lacustre. |
| 3b. Flowers and fruit in short clusters (Gooseberry) [— 4.] | |
| 4a. Ovary and fruit prickly and bristly | Gooseberry, Ribes cynosbati. |
| 4b. Ovary and fruit smooth, or sometimes a little glandular [— 5.] | |
| 5a. Stamens equaling the ovate calyx-lobes in length, or a very little
longer [— 6.] | |
| 5b. Stamens distinctly longer than the linear calyx-lobes [— 7.] | |
| 6a. Leaves glabrous beneath, or nearly so | Gooseberry, Ribes oxyacanthoides. |
| 6b. Leaves softly pubescent beneath | Gooseberry, Ribes oxyacanthoides var. calcicola. |
| 7a. Flowers, including the stamens, about 15 mm. long | Gooseberry, Ribes gracile. |
| 7b. Flowers, including the stamens, about 8 mm. long | Gooseberry, Ribes rotundifolium. |
| 8a. Calyx prolonged above the ovary into a tube which is longer
than the sepals [— 9.] | |
| 8b. Calyx-tube shorter than the ovary or none [— 10.] | |
| 9a. Flowers greenish-yellow, inconspicuous; calyx-tube narrowly
bell-shape | Black Currant, Ribes floridum. |
| 9b. Flowers bright yellow, conspicuous; calyx-tube narrow, with
spreading lobes | Golden Currant, Ribes aureum. |
| 10a. Ovary and berry bristly with glandular hairs | Skunk Currant, Ribes prostratum. |
| 10b. Ovary and fruit smooth, or with sessile glands [— 11.] | |
| 11a. Leaves dotted beneath with resinous glands | Black Currant, Ribes hudsonianum. |
| 11b. Leaves glabrous or pubescent beneath, without resinous glands | Red Currant, Ribes triste. |
| 12a. Flowers minute, yellowish, without petals, in the axils of the
leaves (1-2 dm. high; flowers in spring) | Golden Saxifrage, Chrysosplenium americanum. |
| 12b. Flowers large, solitary, terminating erect stalks (leaves
mostly basal; flowers white, in late summer; flower-stalks 1-5 dm.
high) (Grass-of-Parnassus) [— 13.] | |
| 12c. Flowers in terminal racemes, panicles, or clusters [— 15.] | |
| 13a. Flowers less than 2 cm. wide; leaves narrowed to the base | Grass-of-Parnassus, Parnassia parviflora. |
| 13b. Flowers 2-3.5 cm. wide; leaves rounded or cordate at the base [— 14.] | |
| 14a. A 3-cleft scale at the base of each petal | Grass-of-Parnassus, Parnassia caroliniana. |
| 14b. A many-cleft (9-15) scale at the base of each petal | Grass-of-Parnassus, Parnassia palustris. |
| 15a. Leaves linear to oblanceolate, 3 times as long as broad, or more,
and pinnately veined (Saxifrage) [— 16.] | |
| 15b. Leaves broadly ovate to nearly circular, frequently cordate at the
base, and always palmately veined or lobed [— 20.] | |
| 16a. Leaves basal; the flower-stalk bearing no leaves except small
ones at the base of its branches [— 17.] | |
| 16b. Flower-stalk leafy below (1-3 dm. high; flowers yellow,
summer) [— 18.] | |
| 17a. Petals white; sepals erect; leaves conspicuously toothed, 3-10 cm.
long (1-3 dm. high; spring) | Saxifrage, Saxifraga virginiensis. |
| 17b. Petals greenish; sepals reflexed; leaves minutely toothed or
entire, 10-30 cm. long (5-10 dm. high; spring) | Saxifrage, Saxifraga pennsylvanica. |
| 18a. Leaves with 3 sharp teeth at the apex | Saxifrage, Saxifraga tricuspidata. |
| 18b. Leaves with numerous teeth or entire [— 19.] | |
| 19a. Leaves linear, chiefly on the stem | Saxifrage, Saxifraga aizoides. |
| 19b. Leaves spatulate, chiefly in a basal rosette | Saxifrage, Saxifraga aizoon. |
| 20a. Stamens 5 (leaves mostly basal; flowers greenish or purplish
in late spring, on stalks 5-10 dm. high) (Alum Root) [— 21.] | |
| 20b. Stamens 10 (flowers white, in spring) [— 23.] | |
| 21a. Flowers regular | Alum Root, Heuchera americana. |
| 21b. Flowers irregular, the calyx oblique, longer on the upper side than
on the lower [— 22.] | |
| 22a. Stamens projecting beyond the calyx | Alum Root, Heuchera hirsuticaulis. |
| 22b. Stamens not projecting beyond the calyx | Alum Root, Heuchera hispida. |
| 23a. Stem-leaves alternate or none [— 24.] | |
| 23b. Stem with a pair of opposite leaves (2-4 dm. high) | Bishop's Cap, Mitella diphylla. |
| 24a. Petals deeply fringed (1-2 dm. high) | Bishop's Cap, Mitella nuda. |
| 24b. Petals entire (1-3 dm. high) | False Mitrewort, Tiarella cordifolia. |
Shrubs, with alternate simple leaves; sepals, petals, and stamens each 4; ovary 2-lobed.
Trees, with broad, palmately veined and lobed leaves, and minute flowers in dense spherical heads.