882 ERICACEAE 



3. DENDRIUM Desv. 



Low evergreen shrubs, with much branched stems. Leaves alternate or opposite : blades 

 leathery, entire. Flowers perfect, in terminal corymbs, pedicelled. Calyx persistent : 

 sepals 5, rigid. Corolla white or pink : petals 5, sessile, imbricated. ' Stamens 10, exserted. 

 Filaments filiform, glal)rous. Anthers awnless, opening lengthwise. Disk 10-lobed. 

 Ovary 2-5-celled. United styles straight. Stigma truncate. Ovules numerous. Capsule 

 ovoid, septicidally 2-5-valved. {_LeiophyUum Pers. ] Sand Myrtle. 



Leaves mainly opposite ; blades oval or broadly oblong : lobes of the capsules toothed on back. 



1. D. prostratum. 

 Leaves mainly alternate : blades oblong : capsules smooth or nearly so. 



Leaf-blades 4-8 mm. long : filaments nearly twice as long as the petals : capsules 



about thrice as long as the sepals. 2. D. buxifolium. 



Leaf-blades 1-1.5 cm. long : filaments about as long as the petals : capsules about 



twice as long as the sepals. 3. D. Jhigeri. 



1. Dendrium prostratum (Loud.) Small. An evergreen shrub 1-2 dm. tall, with 

 diffuse and depressed branches. Leaves mainly opposite ; blades leathery, oval or broadly 

 oblong, 4-7 mm. long, obtuse, revolute, lustrous above, pale and dull beneath, narrowed 

 into petioles 1-2 mm. long ; flower-clusters loose or dense : bracts mostly oblong-ovate, ob- 

 tuse : pedicels 5-8 mm. long, minutel}^ glandular : sepals variable, lanceolate to linear, 

 obtusish : corolla white ; petals oval-oblong or sometimes somewhat ovate, 3.5 mm. long, 

 obtuse : filaments club-shaped, longer than the petals : capsules broadly ovate or orbicular- 

 ovate, 2.5-3 mm. long, somewhat lobed, the lobes toothed on the back, more than twice as 

 long as the sepals, commonly elevated on a disk-like stipe. 



On rocky mountain summits, North Carolina and Tennessee. Spring. 



2. Dendrium buxifolium (Berg.) Desv. An evergreen shrub 0.5-5 dm. tall, with 

 erect or spreading much-branched stems. Leaves mainly alternate ; blades leathery, ob- 

 long, obtusish or acutish, lustrous above, paler and dull beneath, narrowed into petioles 

 about 1 mm. long: flower clusters dense : bracts oblong or nearly so, 1-1.5 mm. long: 

 pedicels 2-6 mm. long, glabrous or very sparingly glandular : sepals oblong-lanceolate, 1 

 !nm. long, obtusish : corolla white; petals oblong-ovate, 2-2.5 mm. long, obtuse : filaments 

 club-shaped, nearly twice as long as the jietals : capsules ovoid, 3 mm. long, glabrous or 

 nearly so, prominently lobed, about thrice as long as the sepals. 



In sandy pine lands, New Jersey to Florida. Spring. 



3. Dendrium Hugeri Small. An evergreen shrub 2-4 dm. tall, with erect much- 

 branched stems. Leaves mainly alternate; blades leathery, oblong, 1-1.5 cm. long, 

 lustrous and dark green, joaler beneath, obtuse, revolute, somewhat obliquely narrowed 

 into petioles 1-2 mm. long : flower-clusters dense : bracts oblong-ovate, 3 mm. long, 

 obtuse: pedicels 5-10 mm. long, minutely glandular: sepals lanceolate, almost 1 mm. 

 long, acute : corolla white ; petals ovate, 4 mm. long, obtuse : filaments club-shaped, as 

 long as the petals: capsules ovoid, 3.5-4 mm. long, glabrous or nearly so, obtusely lobed, 

 twice as long as the sepals, abruptly contracted into the stoutish style which is about as long 

 as the capsule-body. 



On cliffs and rocky mountain summits. North Carolina. 



4. AZALEA L. 



Shrubs, with erect irregularly branching stems. Leaves alternate, deciduous : blades 

 entire or bristle-toothed. Flowers perfect, in terminal clusters. Sepals 5. Corolla 

 funnelform, of various colors : tube narrow, elongated : lobes 5, unequal, spreading, dis- 

 posed in 2 lips. Stamens 5, or rarely 10, conspicuously exserted. Filaments often col- 

 ored, declined. Anthers awnless, opening by terminal pores. Ovary 5-celled. Styles 

 declined, long-exserted. Ovules numerous in each cavity. Capsule elongated, septicidally 

 5-valved. 



Corollas expanding before the leaves. 



Corolla red. orange or yellow. 1. A. lutea. 



Corolla pink or white. 



Leaf-blades canescent beneath : corolla-tube glandular-pubescent. 2. A. canesceiis. 



Leaf-blades strigose especially on the midnerve beneath: corolla-tube hirsute. 3. A.nudiflora. 

 Corollas expanding after the leaves. 



Leaf-blades densely white-tomentose beneath. 4. A. Candida. 



Leaf-blades glabroiis or with scattered hairs beneath. 

 A. Midnerve strigose beneath at maturity. 



a. Corolla-tube less than 3 cm. long : eastern species. 5. A. inscosa. 



