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2. Gymnospermae

1 Leaves pinnately compound, leaflets linear; dioecious; stem below ground, or its leaf-bearing apex exposed; Florida and Georgia.   1 Zamiaceae
+ Leaves simple, fan-shaped, needlelike, or scalelike; dioecious or monoecious; stem aboveground; widespread.   (2)
2 (1) Leaves deciduous, fan-shaped, dichotomously veined; ovules 2 at ends of long stalks, often only 1 maturing.   2 Ginkgoaceae
+ Leaves mostly evergreen (deciduous in Larix and usually in Taxodium, often ephemeral and not photosynthetic in Ephedra), needlelike or scalelike, not dichotomously veined; ovules (and seeds) 1--20 on cone scales or 1 on short stalks.   (3)
3 (2) Longest internodes 2--10 cm (shorter at bases of branches); pollen cones compound, each sporangiophore subtended by a pair of bracteoles; seeds inserted on axis of seed cone, subtended by several pairs or whorls of papery, herbaceous, or fleshy bracts; shrubs (sometimes clambering), neither resinous nor fragrant; dry areas in w United States (se Texas to Oregon and California).   6 Ephedraceae
+ Longest internodes 0--1 cm; pollen cones simple, the individual sporophylls not bracteate (usually few sterile bracts at base of cone); seeds inserted on scales of seed cone, scales woody (fleshy and coalescent in Juniperus), or the seeds solitary and not enclosed by bracts or scales in Taxaceae; shrubs or trees, usually resinous and fragrant; widespread.   (4)
4 (3) Seed 1, subtended by but not concealed by inconspicuous sterile bracts, with fleshy or juicy arils; leaves needlelike, spreading in 1 plane ("2-ranked") (except on erect shoots), without resin canals.   5 Taxaceae
+ Seeds 1--400 in woody or fleshy cones, enclosed by conspicuous cone-scales, without arils (if cones fleshy then leaves not spreading in 1 plane); leaves needlelike or scalelike, spreading in 1 plane or not, with or without resin canals.   (5)
5 (4) Foliage leaves needlelike, alternate or fascicled, individually abcising from branchlets when shed (except that fascicles in Pinus are shed as units); cone scales imbricate, seeds 2 per scale.   3 Pinaceae
+ Foliage leaves needlelike or scalelike, alternate, opposite, or whorled, persistent on branchlets (but most branchlets shed with age); cone scales valvate or imbricate (if imbricate then leaves opposite and scalelike), seeds 1--20 per scale.   4 Cupressaceae


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