«■? 



DIVISION INTO FAMILIES AND GENERA. 43 



Husk not dividing naturally. Walnut and Butternut. IV. 1. 

 Husk of the fruit dividing naturally. Hickory. IV. 2. 



("Bark of thin, tough, horizontal fibres ; aments simple ; scale of the fer- 

 _ 9 J tile catkins 3-flowered. Birch. V.. 1. 



} Bark not of tough fibres ; aments on branched stalks ; scale of the fer- 

 L tile catkins 2-rlowered. Alder. V. 2. 



{ Leaves lance-shaped, serrate. Wax Myrtle and Sweet Gale. VI. 1. 

 I Leaves sinuate-pinnatifid. Sweet Fern. VI. 2. 



j Stamens 8 — 30, or more ; leaves 3-angled or roundish. Poplar. VIII. 1. 

 ( Stamens 2 — 7 ; leaves mostly long, slender. Willow. VIII. 2. 



Flowers perfect ; fruit a samara. Elm. X. 1. 

 55. \ Flovyers sterile, or perfect, on one or different trees ; fruit a drupe. Net- 

 tle Tree. X. 2. 



f Anthers 4-celled ; fruit-stalk fleshy; leaves often 3-lobed. Sassafras. 

 XII. 1. 

 Anthers 2-celled ; fruit-stalk not fleshy ; leaves entire. Benzoin. 

 ^ XII. 2. 



["Leaves thorny, leathery, evergreen. Holly. XVI. 1. 

 Leaves unarmed ; petals 4 — 5, distinct; stamens 4—5. Nemopanthus. 



57. < XVI. 2. 



I Leaves unarmed ; petals united, mostly 6-parted ; stamens 4 — 6. Wm- 

 L ter Berry, Prinos. XVI. 3. 



( Flowers in globular heads. Button Bush. XVII. 1. 



58. < Flowers 2 on each double ovary ; berry of 2 united ovaries. Partridge 

 ( Berry, Mitchella. XVII. 2. 



( Stamens 4. Trailing, evergreen. Twin Flower, Linn.ea. XVIII. 1. 

 ' I Stamens 5. 60. 



["Stem not woody. Drupe 3-celled, 3-seeded. Feverwort. XVIII. 2. 

 I Stem woody. Berry 2 — 3-celled, few-seeded ; flowers two-fold, or in 

 60.-^ whorls. Honeysuckle, Lonicera. XVIII. 3. 



I Stem woody. Berry 2-celled, many-seeded. Bush Honeysuckle, Di- 



l ERVILLA. XVIII. 4. 



ri $ Leaves pinnate. Elder. XIX. 1. 

 ( Leaves simple. Viburnum. XIX. 2. 



i Petals united. 03. 

 02. 



>\ 



Petals distinct or nearly so. 70. 



! Corolla somewhat funnel-shaped or bell-shaped. 04. 

 Corolla salver-shaped. 65. 

 Corolla ovoid. 66. 



,,. { Stamens 5 or 6. Azalea. XX. 9. 

 ' ( Stamens 10. Rhododendron. XX. 9. 



Rt . $ Anthers resting in 10 cavities of the corolla. Kalmia. XX. 10. 

 ( Anthers free, calyx double. May Flower, Epigjea. XX. 6. 



! Fruit a berry, formed of the fleshy calyx. Chequer-berry. XX. 7. 

 Fruit a drupe, formed of the ovary, 5-seeded. Bear-berry. XX. 8. 

 Fruit a 5-celled, 5-valved capsule. 67. Andromeda Tribe. XX. 1. 



P_ S Anthers ending in awns or bristles. 68. • 

 ' \ Anthers not ending 1 in awns. 69. 



