The Manual of the Botany of the Northern United States / Including the District East of the Mississippi and North of North Carolina and Tennessee

by Asa Gray

Tribe III. ERICEÆ. Corolla persistent, becoming scarious. Capsule septicidal.

12. Calluna. Corolla bell-shaped, 4-parted. Leaves minute, opposite, imbricate.

Tribe IV. RHODODENDREÆ. Fruit a septicidal capsule. Corolla deciduous.

[*] Anther-cells opening by a hole or chink at the top.

[+] Flowers not from scaly buds; the bracts leaf-like or coriaceous.

13. Bryanthus. Corolla ovate or urn-shaped. Leaves narrow and heath-like.

14. Kalmia. Corolla broadly bell-shaped or wheel-shaped, with 10 pouches receiving as many anthers. Leaves oblong or linear.

[+][+] Flowers developed from large scaly buds, the scales or bracts caducous.

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

16. Rhododendron. Flowers usually 5-merous. Corolla bell-shaped or funnel-form, lobed or parted, often somewhat irregular. Leaves deciduous or evergreen.