CLASS II. GYMNOSPÉRMÆ.
Plants in which the pistil is represented by an open scale instead of a body with a closed ovary, as in Class I.
Order XLI. CONÍFERÆ. (Pine Family.)
As far as the number of species is concerned, this is the largest order of trees and shrubs of temperate and cold-temperate regions. The order is of the greatest importance, both on account of the valuable timber it furnishes and for its resinous secretions, turpentine and resin.
Genus 93. PÌNUS. (The Pines.)
Leaves needle-shaped, 1 to 15 in. long, almost cylindric, 2, 3, or 5 together in clusters, with a sheath, more or less persistent, at the base. Flowers monœcious, both staminate and pistillate in catkins, usually insignificant and unnoticeable. In spring. Fruit a cone, persistent and formed of more or less woody, overlapping scales.
| * Leaves usually 5 together in bundles. (A.) | ||||
| A. Leaves 6 in. or more long, glaucous green and very pendulous | 1. | |||
| A. Leaves under 4 in. long. (B.) | ||||
| B. Cones over 10 in. long, on stalks 3 in. long, pendulous when ripe | 2. | |||
| B. Cones 4 to 10 in. long. (C.) | ||||
| C. Scales of cones thin, unarmed | 3, 4. | |||
| C. Scales of cones thick and woody, obtuse, 1 in. broad | 5. | |||
| B. Cones under 4 in. long; scales slightly hooked but pointless | 6. | |||
| * Leaves usually in threes, rarely in twos; scales of cones with spines or prickles. (D.) | ||||
| D. Scales of cones with short, rigid, straight spines; leaves 6 to 10 in. long | 7. | |||
| D. Scales with sharp, bent prickles. (E.) | ||||
| E. Leaves over 5 in. long, sometimes 15 in. long | 8, 9. | |||
| E. Leaves 3 to 5 in. long, rigid and flattened, from short sheaths, | 10. | |||
| * Leaves usually in twos; cones rarely over 3 in. long. (F.) | ||||
| F. Leaves over 3 in. long. (G.) | ||||
| G. Cone-scales with dull spines | 11. | |||
| G. With small or minute, persistent prickles | 12, 13, 14. | |||
| G. With no prickles, or small ones, early deciduous | 15, 16. | |||
| F. Leaves 3 in. or less long. (H.) | ||||
| H. Cone-scales with straight or slightly curved, rigid spines | 17. | |||
| H. Cone-scales with stout, recurved spines | 18, 19. | |||
| H. Cone-scales with small prickles which are early deciduous | 20. | |||
| H. Cone-scales without spines or prickles | 21, 22. | |||
P. excélsa.