12a. Racemes bractless, or bracted only at the base (1-4 dm. high) --14.

12b. Raceme with a bract at the base of each flower (flowers white or yellowish) --17.

13a. Corolla 4 mm. wide =Forget-me-not, Myosotis laxa.=

13b. Corolla 6-8 mm. wide =Forget-me-not, Myosotis scorpioides.=

14a. Calyx-lobes all of equal length (summer) =Scorpion Gra.s.s, Myosotis arvensis.=

14b. Calyx-lobes distinctly unequal in length (spring) =Scorpion Gra.s.s, Myosotis virginica.=

15a. Corolla-lobes denticulate =Pucc.o.o.n, Lithospermum angustifolium.=

15b. Corolla-lobes entire --16.

16a. Flowers sessile; stem softly p.u.b.escent =Pucc.o.o.n, Lithospermum canescens.=

16b. Flowers on pedicels 2-5 mm. long; stem hispid or bristly =Pucc.o.o.n, Lithospermum gmelini.=

17a. Corolla white; fruit brown and wrinkled (weed 2-4 dm. high; spring and summer) =Corn Gromwell, Lithospermum arvense.=

17b. Corolla yellowish-white; fruit white and smooth (5-10 dm. high) --18.

18a. Corolla distinctly surpa.s.sing the calyx in length (spring and summer) =Corn Gromwell, Lithospermum officinale.=

18b. Corolla equaling or shorter than the calyx (spring) =Wild Gromwell, Lithospermum latifolium.=

l.a.b.i.aTAE, the Mint Family

Herbs with opposite leaves, square stems, and usually aromatic odor; flowers irregular, with united petals, or almost regular; stamens 2 or 4, attached to the tube of the corolla; ovary deeply 4-lobed, with a single style.

1a. Stamens 2 --2.

1b. Stamens 4 --15.

2a. Corolla regular or nearly so; flowers white, in dense axillary cl.u.s.ters; plants usually of wet grounds (2-8 dm. high; summer and autumn) --3.

2b. Corolla distinctly irregular and more or less 2-lipped --7.

3a. Calyx-teeth short, triangular, acute or obtuse (Bugle Weed) --4.

3b. Calyx-teeth narrow, ac.u.minate or cuspidate (Water h.o.a.rhound) --5.

4a. Stems and stolons bearing tubers =Bugle Weed, Lycopus uniflorus.=

4b. Stems and stolons not bearing tubers =Bugle Weed, Lycopus virginicus.=

5a. Leaves serrate; calyx-teeth sharp-pointed --6.

5b. Leaves coa.r.s.ely incised; calyx-teeth awn-tipped =Water h.o.a.rhound, Lycopus america.n.u.s.=

6a. Corolla twice as long as the calyx; leaves narrowed at the base =Water h.o.a.rhound, Lycopus rubellus.=

6b. Corolla barely longer than the calyx; leaves sessile or nearly so =Water h.o.a.rhound, Lycopus lucidus var. america.n.u.s.=

7a. Corolla blue, 3-4 mm. long; flowers in loose axillary cl.u.s.ters (1-4 dm. high; summer) (Pennyroyal) --8.

7b. Corolla 8-40 mm. long --9.

8a. Leaves serrate =Pennyroyal, Hedeoma pulegioides.=

8b. Leaves linear, entire =Pennyroyal, Hedeoma hispida.=

9a. Lower lobe of the corolla fringed, very much longer than the upper (5-15 dm. high; corolla pale-yellow; late summer) =Horse Balm, Collinsonia canadensis.=

9b. Lower lobe of the corolla nearly or quite as long as the upper and not fringed --10.

10a. Calyx narrowly tubular; its teeth about equal in size (5-10 dm. high; flowers in dense terminal heads, in summer) --11.

10b. Calyx campanulate, 2 of its teeth different in size from the other 3 (4-8 dm. high; flowers pink-purple, in terminal cl.u.s.ters in summer) --14.

11a. Corolla scarlet =Oswego Tea, Monarda didyma.=

11b. Corolla bright crimson or rose-red =Wild Bergamot, Monarda fistulosa var. rubra.=

11c. Corolla white, pink, pale-purple, or yellowish --12.

12a. Flower-cl.u.s.ters all terminal --13.

12b. Flower-cl.u.s.ters both terminal and axillary =Horse Mint, Monarda punctata.=

13a. Leaves and stem with soft spreading p.u.b.escence =Wild Bergamot, Monarda fistulosa.=

13b. Leaves and stem grayish with fine appressed p.u.b.escence =Wild Bergamot, Monarda mollis.=

14a. Upper calyx-teeth about 3 times as long as the lower =Blephilia, Blephilia hirsuta.=

14b. Upper calyx-teeth but little longer than the lower =Blephilia, Blephilia ciliata.=

15a. Calyx with a distinct protuberance on the back of the upper side (Skullcap) --16.

15b. Calyx without a distinct protuberance --20.

16a. Corolla 5-8 mm. long; flowers in axillary racemes (3-8 dm.