CLASS I. GYMNOSPERMAE 



Trees or shrubs characterized by having the 

 seed not enclosed in an ovary. 



i CYCADALES. Cycad Order. 

 i CYCADACEAE. Cycad Family. 



1 CtCAS SAGO PALM. (C. revoliita*) 



2 ZAMI A COONTIE. (Z. floridana*) 



2 GINKGOALES. Ginkgo Order. 

 t GINKGOACEAE. Ginkgo Family. 



i GfNKGO MAIDENHAIR TREE. (G. blloba*) 



3 FINALES. Pine Order. 



1 TAXACEAE. Yew Family. 

 i TAXUS. 



i a Low, prostrate shrub; native species. 



AMERICAN YEW. (T. canadensis.) 

 b Shrub or small tree not prostrate; cultivated species 



EUROPEAN YEW. (T. baccata.*) 



2 PINACEAE. Pine Family. 



1 ARAUCARIA NORFOLK ISLAND PINE. (A. excelsa*) 



2 PINUS. 



1 a Leaves in clusters of 5, or some in 4*8 2 



b Leaves in clusters of 2 or 3 4 



2 a Leaves 5-8 in. long, drooping, bluish-green; young 



branches glaucous BHOTAN PINE. (P. excelsa*) 



b Leaves 2-5 in. long; young branches not glaucous 3 



3 a Young branches covered with brownish hairs; cones 2-4 



in. long Swiss STONE PINE. (P. cembra*) 



b Young branches not covered with brownish hairs; cones 



3-6 in. long WHITE PINE. (P. strbbus.) 



4 a Leaves in clusters of 3 5 



b Leaves in clusters of 2, or some in 3's 6 



5 a Cultivated tree ; mature cones 4-6 in. long 



WESTERN YELLOW PINE. (P. ponderbsa*) 

 b Native tree; mature cones 2-3 in. long 



PITCH PINE. (P. rigida.) 



6 a Erect or prostrate shrub ; leaves %-2 in. long. 



Swiss MOUNTAIN PINE. (P. montana.*) 

 b Erect trees 7 



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