10 General Key to Families 



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 22B. Rhizome scales "fibrous," i.e., mostly with elongate cells with thinner lateral walls and 



mostly colored outer walls Fam. 17. Aspidiaceae, 50 



21B. Rhizomes hairy but not scaly Fam. 12. Pteridaceae (Microlepia) , 38 



18B. Sori without indusia. 

 23A. Spicular cells i.e., narrow, elongate, thickened cells present among normal cells of the epidermis; 

 blades glabrous and scaleless; rhizome scales clathrate; fronds simple, linear to obovate, entire 



and not lobed, not articulate to the rhizome Fam. 21. Vittariaceae, 106 



23B. Spicular cells absent; blades often hairy or scaly; rhizome scales fibrous or rarely clathrate; fronds 

 simple to compound, articulate to the rhizome or not. 

 24A. Plants normally epiphytic or saxicolous (terrestrial in N eocheiropteris with basally articulate 

 fronds; Platycerium with sporangia acrostichoid, i.e., borne over the whole surface). 



Fam. 20. Polypodiaceae, 96 

 24B. Plants terrestrial; fronds not basally articulate, the sporangia not acrostichoid. 



Fam. 12. Pteridaceae {Pleurosoriopsis and Coniogramme) , 



7B. Fronds 4-foliolate; sporangia enclosed in basal sporocarps; plants aquatic, growing in mud Fam. 22. Marsileaceae, 107 



IB. Free floating, usually not sedentary; leaves entire or 2-lobed Fam. 23. Salviniaceae, 107 



II. Phylum SPERMATOPHYTA Shushi-Shokubutsu Seed Plants 



Plants with true flowers and seeds; female gametophyte developed within the macrosporangium (ovule), at maturity 

 forming, with the enclosed embryonic sporophyte, the seed. 



lA. Ovules naked, borne on the surface of a scale (sporophyll), sometimes arillate; flowers usually unisexual (plants monoecious or 

 dioecious) ; trees or shrubs, mostly evergreen with needlelike, scalelike to subulate or rarely flabellate or pinnately compound 

 leaves; stigmas absent; plants cone-bearing Class 1. Gymnospermae, 109 



IB. Ovules borne within an inclosed cavity (ovary); flowers perfect or unisexual; trees, shrubs, or herbs; leaves various; plants with 

 true flowers consisting of a stigma, style, ovary and stamens plus a floral envelope, or modifications of this condition. 



Class 2. Angiospermae, 118 



Class 1. GYMNOSPERMAE 



lA. Plants with palmlike leaves, dioecious; leaves pinnately compound, leathery, shiny, evergreen; ovules borne on pinnately com- 

 pound naked sporophylls; microsporangia borne in a large terminal cone Fam. 24. Cycadaceae, 109 



IB. Plants with leaves otherwise, not palmlike; leaves simple. 



2A. Leaves flabellate, often deeply bifid at apex, long-petiolate, deciduous Fam. 25. Ginkgoaceae, 109 



2B. Leaves acicular, linear, or scalelike, rarely flat and oblong, sessile or nearly so, evergreen. 

 3A. Ovules 1 to few, enveloped by a relatively soft pulpy drupe or berrylike fruit; cotyledons 2. 



4A. Anthers 2-locular; leaves narrowly lanceolate to oblong, 5-30 mm. wide; ovules solitary Fam. 27. Podocarpaceae, 110 



4B. Anthers 3- to 9-locular; leaves linear, 2.0-3.5 mm. wide. 



5A. Anthers 3-locular; leaves 2-5 cm. long; ovules several, paired Fam. 28. Cephalotaxaceae, 111 



5B. Anthers 4- to 9-locuIar; leaves 1.5-2.5 cm. long; ovules solitary Fam. 26. Taxaceae, 109 



3B. Ovules numerous, borne on scales enclosed in a woody cone; cotyledons 2 or more. 

 6A. Cone-scales spirally arranged; leaves alternate or in fascicles. 



7A. Cone-scales 2-seeded, flattened, bracteate; leaves acicular or linear Fam. 29. Pinaceae, 1 1 1 



7B. Cone-scales 2- to 9-seeded, flattened or peltate, ebracteate; leaves subulate or linear by cohesion of a pair. 



Fam. 30. Taxodiaceae, 1 1 5 

 6B. Cone-scales and leaves opposite or verticillate, the latter scalelike or short-subulate Fam. 31. Cupressaceae, 116 



Class 2. ANGIOSPERMAE 



Subclass 1. MONOCOTYLEDONEAE 



Leaves usually parallel-veined; flowers typically 3-merous, sometimes 6-merous, rarely 4-merous (Stemonaceae). 



lA. Plants with chlorophyll and characteristically with green leaves. 

 2A. Flowers in axils of chaffy or scaly bracts; perianth obsolete or brisde-shaped; ovary superior, 1-locular, 1-ovuled. 



3A. Leaves 2-ranked; internodes hollow; culms round; leaf sheath split Fam. 41. Gramineae, 131 



3B. Leaves 3-ranked; internodes mostly solid; culms predominantly 3-angled; leaf sheath not split Fam. 42. Cyperaceae, 195 



2B. Flowers not in axils of scaly or chaffy bracts; perianth either present or absent. 

 4A. Ovary superior or partly inferior. 



5A. Carpels 2 to many, free, each containing 1 ovule, rarely 6 ovules. 

 6A. Perianth-segments 6. 



7A. Outer 3 perianth-segments sepallike, the inner 3 petallike Fam. 38. Alismataceae, 126 



7B. Perianth-segments all alike Fam. 37. Scheuchzeriaceae, 125 



