xxiv North American Trees 



9. Leaves narrowed at base into stalk; cones pendent with distinc- 

 tive exserted bracts; buds pointed, non-resinous 



PSEUDOTSUGA, p. 63. 



10. Leaves deciduous (persistent in the tropical T. mucronatum) ; 

 2 seeds under each scale; southeastern. TAXODIUM, p. 93. 



10. Leaves persistent; 2-9 seeds under each scale; Pacific Coast 



SEQUOIA, pp. 89, 91. 



1 1. Leaves Yj-l inch long; fruit a seed partially enclosed in a scarlet 

 aril, maturing in 1 year TAXUS, p. 119. 



11. Leaves l-'iVi inches long; fruit a drupelike seed enclosed in a 



green or purple, fleshy covering; maturing in 2 years 



TORREYA, p. 117. 



12. Gone berry-like; leaves scalelike or awl-shaped, both types 

 usually present; seed wingless JUNIPERUS, p. 106. 



12. Gone woody or leathery; leaves scalelike; seed winged. ... 13 



13. Gones globose with peltate scales, 2-20 seeds per scale 14 



13. Gones oblong, thin-scaled, 2-3 seeds per scale 15 



14. Gone woody, over Yz inch across, of 6-12 scales; 6-20 seeds 

 per scale GUPRESSUS, p. 98. 



14, Gone leathery, V^-Vi inch across, of 4-8 scales; 2-5 seeds 

 per scale GHAMAEGYPARIS, p. 98. 



15. Gones %-l Vi inches long, 6-scaled; Far West 



LIBOGEDRUS, p. 95. 



15. Gones 1/3-K2 inch long, 8-12 scaled THUJA, p. 97. 



B. MONOGOTYLEDONS 



LEAVES WITH PARALLEL VEINS, ALTERNATE, SIMPLE, 



AND PERSISTENT 



1 . Leaves lanceolate and long ; fruit a large capsule . YUGGA, p. 369. 

 1. Leaves fan-shaped, large; fruit a drupelike berry 2 



2. Leaf stalks armed with spines; southwestern 



WASHINGTONIA, p. 371. 



2. Leaf stalks unarmed; southeastern SABAL, p. 371. 



G. DIGOTYLEDONS 

 LEAVES WITH NETTED VEINS OR RARELY ABSENT 



a. Leaves and buds opposite 



b. Leaves compound Ij P* xxv 



b. Leaves simple Hj P- xxv 



a. Leaves and buds alternate 



c. Leaves compound Ill, p. xxvi 



c. Leaves simple 



d. Leaves persistent IV, p. xxvi 



d. Leaves deciduous V, p. xxviii 



