GENUS i. 



HEATH FAMILY. 



677 



About 5 species, natives of the north temperate and sub-arctic zones. Besides the following 

 2 others occur on the Pacific Coast. Types species : Ledum palustre L. 



Leaves linear, i"- 3 " wide; stamens about 10. ! L decumbens 



Leaves oblong, 3 "-8" wide ; stamens 5-7. 2. L. groenlandicum. 



i. Ledum decumbens (Ait.) Lodd. Narrow- 

 leaved Labrador Tea. Fig. 3213. 



L. palustre decumbens Ait. Hort. Kew. 2: 65. 1789. 

 L. decumbens Lodd.; Steud. Nomencl. Ed. 2, 20, 1841. 



A shrub, about i high, the twigs rusty-tomentose. 

 Leaves linear, obtuse, dark green and somewhat rugose 

 above, densely tomentose with brown wool beneath, 

 strongly revolute-margined, J'-f long, i"-2" wide; 

 flowers 3"-5" broad; pedicels very pubescent, 4"-8" 

 long in fruit; stamens 10; capsule obovoid or oval, 

 scurfy, about 2" high and ii" in diameter, nodding; 

 calyx-teeth less than i" long, broadly ovate to half- 

 orbicular, obtuse. 



In bogs, Newfoundland to Maine and Quebec, west to 

 Alaska. Also in northern Asia. In our first edition in- 

 cluded in L. palustre L., of Europe and Asia. Summer. 



2. Ledum groenlandicum Oeder. 

 Labrador Tea. Fig. 3214. 



Ledum groenlandicum Oeder, Fl. Dan. pi. 567. 

 1771. 



Ledum latifolium Ait. Hort. Kew. 2: 65. 1789. 



A shrub, i-4 high, similar to the pre- 

 ceding species, the twigs densely tomentose. 

 Leaves oblong, obtuse, i'-2 r long, 3 "-8" wide, 

 green and slightly rugose above, densely brown- 

 tomentose beneath, strongly revolute-mar- 

 gined ; flowers 4"-5" broad, umbellate or short- 

 corymbose; pedicels brown-canescent or tomen- 

 tose, io"-i2" long and recurved in fruit; 

 stamens 5-7; capsule oblong, canescent, nod- 

 ding, 3"-3i" long, i"-il" in diameter. 



In bogs and swamps, Greenland ; Labrador to 

 British Columbia, Massachusetts, eastern Penn- 

 sylvania, Wisconsin, Saskatchewan and Washing- 

 ton. May-Aug. 



2. AZALEA L. Sp. PI. 150. 1753. 



Erect mostly tall branching shrubs, with alternate thin deciduous leaves. Flowers large, 

 white, purple, yellow, pink, or orange, in terminal umbels developed from cone-like scaly 

 buds. Calyx small or minute, S-parted. Corolla funnelform, the tube mostly narrow, the 

 limb nearly regularly 5-lobed or somewhat 2-lipped. Stamens 5 (rarely 10), exserted, usually 

 declined ; anthers awnless, attached to the filaments by their backs, the cells opening by 

 terminal pores ; styles slender, declined, exserted. Ovary 5-celled ; ovules numerous in the 

 cavities. Capsule oblong or linear-oblong, 5-celled, septicidally 5-valved from the summit, 

 many-seeded. [Greek, dry, from the habitat of one of the original species.] 



About 40 species, natives of North America and Asia. Besides the following, another occurs 

 on the Pacific Coast and 2 or 3 in the Southern States. Type species: Azalea indica L. The genus 

 is included in Rhododendron by some authors. 

 Flowers expanding before or with the leaves. 

 Flowers pink or white. 



Leaves strigose on the midrib beneath ; corolla-tube hirsute. i. A. nudiflora. 



Leaves canescent beneath ; corolla-tube glandular. 2. A. canescens. 



Flowers orange, yellow or red ; leaves canescent beneath. 3. A. lutea. 



Flowers expanding later than the leaves. 



Leaves shining, glabrous beneath. 4. A. arborescens. 



Leaves strigose on the midrib beneath. 5. A. viscosa. 



