NASCULAR PLANTS OF THE YANGTZE VALLEY 

 B. ANGIOSPERMAE 



la. Cotyledons 2: vascular bundles arranged in rings: lvs. net-veined, a. DICOTYLEDONEAE 

 lb. Cotyledons 1: vascular bundles scattered: lvs. usually parallel- 

 veined b. MONOCOTYLE- 



DONEAE, p. 19 



a. DICOTYLEDONEAE 



la. Perianth none, or of a single whorl; or if of two whorls, the inner 



(corolla) of separate petals (1) ARCHICHLAMY- 



DEAE 

 lb. Perianth of two whorls; calyx and corolla both present; the petals 



more or less united (2) METACHLAMY- 



DEAE, p. 16 



(1) Archichlamydeae 



la. Perianth absent, or of a single whorl regarded as the calyx, (lb, 

 p. 10) 

 2a. Fls., at least the staminate or the pistillate ones, in catkins or 

 globose heads: trees or shrubs. 

 3a. Staminate and pistillate fls. both in catkins or globose heads. 

 Fr. a capsule. 



Frtg. spike elongated, cylindric: capsules 1-celled, with 



many hairy-tufted seeds: dioecious trees or shrubs. .. 36. Salicaceae 

 Frtg. spike globose: capsules 2-celled, woody, with 1 or 



2 winged seeds : monoecious trees Liquidambar 



Fr. a fleshy syncarp: a dioecious tree or shrub 37. Myricaceae 



3b. Staminate fls. only in catkins. 



Lvs. pinnately compound, estipulate: fr. drupe-like or nut- 

 like 38. Juglandaceae 



Lvs. simple, with deciduous stipules: fr. a nut. 



Nut small and compressed, or larger and enclosed by a 



leaf -like involucre 39. Betulaceae 



Nut large and partly or wholly enclosed by a scaly or 



bristly involucre 40. Fagaceae 



2b. Fls. not in catkins or globose heads: trees, shrubs, or herbs. 

 4a. Ovary superior: fls. regular. (4b, p. 10) 



5a. Plants with milky or colored sap: lvs. mostly alternate. 

 Ovary 1-celled. 



Fr. a fleshy syncarp or syconium: trees and shrubs with 



milky sap 42. Moraceae 



Fr. a capsule: tall herb with colored sap Macleya 



Ovary 3-celled: fr. a capsule or berry: fls. unisexual 91. Ewphorbiaceae 



5b. Plants with watery sap: lvs. alternate or opposite. 

 6a. Fls. unisexual. (6b, p. 9) 

 7a. Plants aquatic, submersed herbs. 



Lvs. verticillate, dissected into linear divisions; sterile 



fls. with 10-20 stamens: ovary 1-celled: style one. 58. Ceratophyllaceae 

 Lvs. opposite, entire: sterile fls. with one stamen: 



ovary 4-celled : styles two 93. Callitrichaceae 



7b. Plants terrestrial. 



8a. Fr. a samara, drupe, achene or utricle. 



8 



