6a. Stem and leaves glabrous (3-6 dm. high; spring)
=Bluebell, Mertensia virginica.=

6b. Stem and leaves pubescent (4-8 dm. high) --7.

7a. Corolla regular; leaves ovate or ovate-lanceolate (summer)
=Bluebell, Mertensia paniculata.=

7b. Corolla irregular; leaves linear-oblong (summer)
=Blueweed, Echium vulgare.=

8a. Ovary and fruit covered with hooked prickles --9.

8b. Ovary and fruit not prickly --12.

9a. Principal leaves 2.5 cm. wide or more --10.

9b. Principal leaves 2 cm. wide or less (3-8 dm. high; flowers blue or
white, summer) (Stickseed) --11.

10a. Leaves chiefly basal, the racemes on long leafless peduncles
(4-8 dm. high; flowers pale blue, early summer)
=Wild Comfrey, Cynoglossum boreale.=

10b. Stems leafy (8-12 dm. high; flowers white, summer)
=Beggar Lice, Lappula virginiana.=

11a. A bract at the base of each flower =Stickseed, Lappula echinata.=

11b. Racemes without bracts at the base of each flower
=Stickseed, Lappula deflexa var. americana.=

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 Grass, Myosotis arvensis.=

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

15a. Corolla-lobes denticulate =Puccoon, Lithospermum angustifolium.=

15b. Corolla-lobes entire --16.

16a. Flowers sessile; stem softly pubescent
=Puccoon, Lithospermum canescens.=

16b. Flowers on pedicels 2-5 mm. long; stem hispid or bristly
=Puccoon, 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. hig