186b. Leaves not lobed; stem not th.o.r.n.y 1b, in =RHAMNACEAE=, p. 71.
187a. Flowers dark red-purple =ANONACEAE=, p. 40.
187b. Flowers yellow 2a, in =BERBERIDACEAE=, p. 40.
GROUP 2, UNUSUAL PLANTS
1a. Small brown leafless plants, growing as parasites on the tamarack or black spruce =LORANTHACEAE=, p. 25.
1b. Aquatic plants, with all or most of the leaves submerged, or leafless --2.
1c. Aquatic plants, with the leaves or the whole plant floating on or near the surface --20.
1d. Terrestrial or marsh plants, without floating or submerged leaves --29.
2a. Submerged aquatics, without leaves --3.
2b. Submerged aquatics, with the leaves linear or dissected --4.
3a. Flowers showy, yellow or purple =LENTIBULARIACEAE=, p. 105.
3b Flowers small and inconspicuous, sessile, purplish or greenish 3a, in =HALORAGIDACEAE=, p. 79.
4a. Leaves linear or lanceolate, not lobed or dissected --5.
4b. Leaves more or less lobed or dissected --13.
5a. Leaves all basal --6.
5b. Stem-leaves present --7.
6a. Flowers blue, 1 cm. long or more; leaves cylindrical, blunt, hollow, part.i.tioned lengthwise 1a, in =LOBELIACEAE=, p. 113.
6b. Flowers yellow; leaves minute =LENTIBULARIACEAE=, p. 105.
6c. Flowers white, in cl.u.s.ters; leaves linear-lanceolate, acute, not hollow 1b, in =ALISMACEAE=, p. 3.
6d. Flowers greenish, solitary at the end of elongated peduncles; leaves very long and ribbon-like, flat or trough-shape 1a, in =HYDROCHARITACEAE=, p. 3.
6e. Flowers minute, whitish or lead-color, in heads =ERIOCAULACEAE=, p. 9.
7a. Leaves alternate --8.
7b. Leaves opposite --10.
7c. Leaves whorled --12.
8a. Leaves with thin sheathing stipules 1b, in =NAJADACEAE=, p. 2.
8b. Leaves without stipules --9.
9a. Flowers greenish, in a head =SPARGANIACEAE=, p. 2.
9b. Flowers pale yellow 1b, in =PONTEDERIACEAE=, p. 10.
10a. Leaves serrate 2b, in =NAJADACEAE=, p. 2.
10b. Leaves entire --11.
11a. Leaves 2 cm. long or less =CALLITRICHACEAE=, p. 68.
11b. Leaves thread-like, 2-8 cm. long 2a, in =NAJADACEAE=, p. 2.
11c. Leaves linear to elliptical, more than 2 cm. long 1b, in =NAJADACEAE=, p. 2.
12a. Leaves in whorls of 3, abruptly widened at the base 2b, in =NAJADACEAE=, p. 2.
12b. Leaves in whorls of 3, widest near the middle 1b, in =HYDROCHARITACEAE=, p. 3.
12c. Stems straight and erect, at leaves the flowers emerged; leaves in whorls of 4 or more 2a, in =HALORAGIDACEAE=, p. 79.
13a. Leaves with numerous small bladders attached, each bladder 1-3 mm.
long =LENTIBULARIACEAE=, p. 105.
13b. Leaves without bladders --14.
14a. Leaves alternate --15.
14b. Leaves opposite or whorled --18.
15a. Delicate and rare plants growing attached to stones in running water =PODOSTEMACEAE=, p. 48.
15b. Plants 2 dm. high or more, with roots in mud or sand --16.
16a. Leaves once-pinnate --17.
16b. Leaves 2-3 times pinnate 15b, in =UMBELLIFERAE=, p. 81.
16c. Leaves palmately dissected 1b, in =RANUNCULACEAE=, p. 35.
17a. Taste peppery or mustardy 34, in =CRUCIFERAE=, p. 45.
17b. Taste not peppery or mustardy 1a, in =HALORAGIDACEAE=, p. 79.
18a. Leaves pinnately compound 3b, in =HALORAGIDACEAE=, p. 79.
18b. Leaves palmately compound --19.