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.