626 ERICACEAE (HEATH FAMILY^ 



Subfamily I. PYROLOIDEAE (Pyrola Subfamily) 



Calyx free from the ovary. Corolla polypetalous. Anthers extrorse in the 

 bud, opening by pores at the base (inverted in the flower). Seeds with a loose 

 and translucent cellular coat much larger than the nucleus. 



Tribe I. CL^THREAE. Shrubs or trees, with deciduous foliage (in ours). Pollen-grains simple. 

 Capsule 3-celled. 



1. Clethra. Sepals and petals 5. Stamens 10. Style 3-cleft at the apex. 



Tribe II. PYR6LEAE. Herbaceous or nearly so, with evergreen foliage. Pollen-grains compound. 

 Capsule .^(rarely 4)-celled. 



2. Chimaphila. Stems leafy. Flowers corymbed or umbeled. Petals widely spreading. Style 



very short and top-shaped. Valves of the capsule smooth on the edges. 



3. Moneses. Scape 1-flowered. Petals wdely spreading. Style straight, exserted ; stigma 



5-rayed. Valves of the capsule smooth on the edges. 



4. Pyrola. Acaulescent. Flowers in a raceme. Petals not widely spreading. Filaments awl- 



shaped. Style long. Valves of the capsule cobwebby on the edges. 



Subfamily II. MONOTROPOIDEAE (Indian Pipe Subfamily) 



Flowers nearly as in Subfamily I or III, but the plants herbaceous, root-para- 

 sitic or saprophytic, entirely destitute of green foliage, and with the aspect of 

 Beech Drops. Seeds as in Subfamily I. 



* Corolla of 4 or 5 separate petals ; calyx imperfect or bract-like. 



5. Monotropa. Petals narrow. Anthers kidney-shaped, opening across the top. 



* * Corolla gamopetalous ; anthers 2-celled. 



6. Pterospora. Corolla ovoid, 5-toothed. Anthers 2-awned on the back, opening lengthwise. 



7. MonotropSiS. Corolla broadly bell-shaped, 5-lobed. Anthers opening at the top. 



Subfamily III. ERICOfDEAE (Heath Subfamily) 



Calyx free from the ovary. Corolla gamopetalous, rarely polypetalous, 

 hypogynous. — Shrubs or small trees. 



Tribe I. RHODODENDREAE. Fruit a septicidal capsule. Corolla deciduous. 



* Flowers developed from scaly buds. 



+■ Scales or bracts caducous ; anther-cells opening by a hole or chink at the top. 



8. Ledum. Corolla regular, all 5 petals nearly separate. Stamens 5-10. Leaves evergreen. 



9. Rhododendron. Flowers usually 5-merous. Corolla bell-shaped or funnel-form, lobed or 



i:>arted, often somewhat irregular. Leaves deciduous or evergreen. 



10. Menziesia. Corolla globular-bell-shaped, 4-toothed. Stamens 8. Leaves deciduous, 

 -»- +■ Bud-scales firm and persistent ; anther-cells opening lengthwise ; leaves evergreen. 



11. Leiophyllum. Corolla of 5 separate petals. Stamens 10, exserted. 



12. Loiseleuria. Corolla deeply 5-cleft. Stamens 5, included. 



* * Flowers not from scaly buds ; the bracts leaf-like or coriaceous, 



13. Kalmia. Corolla broadly bell-shaped or wheel-shaped, with 10 pouches receiving as many 



anthers. Leaves oblong or linear. 



14. Phyllodoce. Corolla ovoid or urn-shaped. Leaves narrow and heath-like. 



Tribe II. ANDROM^DEAE. Fruit a loculicidal capsule (berry-like in no. 22). Corolla deciduous, 



* Calyx dry, not becoming fleshy after flowering. 

 +■ Anther-cells opening only at the top ; corolla not .salver-shaped. 

 +-•• Corolla campanuiate, 4-5-lobed or -parted ; heath-like, with acerose imbricated leaves. 

 t5. Cassiope. Calyx of ovate imbricated sepals. Capsule globular-ovoid, 4-5-valved, the valves 

 2-cleft. 



