10b. Leaves dull on the upper side; sepals one-fourth as long as the petals, or a little shorter --11.

11a. Leaf-blades mostly shorter than their petioles, thick and firm =Shin-leaf, Pyrola chlorantha.=

11b. Leaf-blades thin, usually longer than their petioles =Shin-leaf, Pyrola elliptica.=

12a. Petals nearly or quite separate from each other --13.

12b. Petals united into a gamopetalous corolla, the tube of which is as long as or longer than the lobes --18.

13a. Leaves opposite or whorled; stems herbaceous or nearly so (summer) --14.

13b. Leaves alternate; stems shrubby (early summer) --16.

14a. Flowers solitary; leaves broadly ovate to nearly circular (1 dm. high; flower white) =One-flowered Wintergreen, Moneses uniflora.=

14b. Flowers in cl.u.s.ters; leaves narrow (stems trailing, 1-3 dm.

high; flowers white or pinkish) --15.

15a. Leaves broadest above the middle, green =Prince's Pine, Chimaphila umbellata.=

15b. Leaves broadest below the middle, spotted with white =Spotted Wintergreen, Chimaphila maculata.=

16a. Leaves 2-5 cm. long, densely woolly beneath (5-10 dm. high; flowers white) =Labrador Tea, Ledum groenlandic.u.m.=

16b. Leaves 1-2 cm. long, pale beneath but not wholly (creeping; flowers pink) (Cranberry) --17.

17a. Leaves acute =Cranberry, Vaccinium oxycoccos.=

17b. Leaves obtuse =Cranberry, Vaccinium macrocarpon.=

18a. Leaves opposite or whorled; corolla saucer-shape (shrubs 3-8 dm. high; flowers purple, summer) --19.

18b. Leaves alternate; corolla bell-shape or salver-form --20.

19a. Branches and twigs cylindrical, not angled =Sheep Laurel, Kalmia angustifolia.=

19b. Branches and twigs with 2 sharp angles =Swamp Laurel, Kalmia polifolia.=

20a. Plants prostrate, or with a few ascending branches only (flowers white or pink) --21.

20b. Plants erect or ascending --23.

21a. Flowers 10-20 mm. long, very fragrant (early spring) =Trailing Arbutus, Epigaea repens.=

21b. Flowers 4-5 mm. long (late spring) --22.

22a. Leaves spatulate, broadest beyond the middle =Bearberry, Arctostaphylos uva-ursi.=

22b. Leaves oval, broadest at the middle =s...o...b..rry, Chiogenes hispidula.=

23a. Leaves linear, white beneath, their margins strongly revolute (shrub 3-8 dm. high; flowers white, late spring) =Bog Rosemary, Andromeda glaucophylla.=

23b. Leaves oblong, scurfy beneath with rusty scales (bog shrub 4-10 dm.

high; flowers white, in spring) =Leatherleaf, Chamaedaphne calyculata.=

23c. Leaves smooth, p.u.b.escent, or resinous beneath, but not scurfy nor white --24.

24a. Low shrubs 10-15 cm. high, erect from a creeping rootstock; leaves with the taste of wintergreen (flowers white or pink, summer) =Wintergreen, Gaultheria proc.u.mbens.=

24b. Bushy shrubs 3-8 dm. high; leaves dotted beneath with yellowish resinous dots; ovary 10-celled (flowers greenish-pink, spring) =Huckleberry, Gaylussacia baccata.=

24c. Shrubs 1 dm. to 3 m. high; leaves not resinous-dotted beneath; ovary 5-celled (flowers white or greenish-pink, spring or early summer) --25.

25a. Corolla bell-shape, the stamens projecting beyond it (5-15 dm.

high) =Deerberry, Vaccinium stamineum.=

25b. Corolla cylindrical or urn-shape, the stamens not projecting --26.

26a. Filaments hairy (Blueberry) --27.

26b. Filaments glabrous (Bilberry) --32.

27a. Low bushy shrubs, usually less than 5 dm. and never more than 1 m.

high --28.

27b. Tall erect shrubs, 1-4 m. high --31.

28a. Foliage p.u.b.escent =Blueberry, Vaccinium canadense.=

28b. Foliage glabrous --29.

29a. Leaves pale-green and glaucous, entire or nearly so =Blueberry, Vaccinium vacillans.=

29b. Leaves bright-green, distinctly serrulate --30.

30a. Fruit blue =Blueberry, Vaccinium pennsylvanic.u.m.=

30b. Fruit black =Blueberry, Vaccinium pennsylvanic.u.m var. nigrum.=

31a. Leaves downy beneath; fruit black =Blueberry, Vaccinium atrococc.u.m.=

31b. Leaves smooth or minutely p.u.b.escent beneath; fruit blue =Blueberry, Vaccinium corymbosum.=

32a. Full-grown leaves less than 2.5 cm. long; low much-branched shrubs, mostly less than 5 dm. high --33.

32b. Full-grown leaves more than 2.5 cm. long; shrubs usually a meter high or more --34.

33a. Leaves entire; petals usually 4.