vi Key to the Families 



SUBCLASS II. DICOTYLEDONS. 



Leaves mostly netted-veined ; flowers seldom 3-merous or 

 6-merous, usually 4-merous or 5-merous. 



Petals separate and distinct from each other or sometimes wanting, rarely 

 somewhat united. Series 1. CHORIPETALAE. 



Petals partly or wholly united, rarely separate or wanting. 



Series 2. SYMPETALAE. 



SERIES I. CHORIPETALAE. 



Petals distinct, at least at base, except in some species of 

 Silene and Crassulaceae. . 



Petals wanting. 



(A) Flowers unisexual, one or both kinds in aments; trees or shrubs. 



Staminate flowers in aments, pistillate becoming a nut. 



Leaves pinnate. JUGLANDACEAE, 96. 



Leaves entire or variously lobed or toothed. FAGACEAE, 104. 



Staminate and pistillate flowers both in aments. 



Leaves opposite; flowers dioecious. GARRYA, 293. 



Leaves alternate. 



Pistillate flowers becoming wax-coated berries. MYRICACEAE, 97. 

 Pistillate flowers becoming capsules. SALICACEAE, 98. 



Pistillate flowers with their scales becoming a woody cone in fruit. 



BETDLACEAE, 103. 



(B) Flowers not in aments. 



* Ovary superior. 



1. HERBS. 

 Calyx and corolla both wanting. 



Flowers perfect, in spikes, these surrounded at base by a conspicuous white 



involucre. ANEMOPSIS, 96. 



Flowers monoecious. 

 Aquatic plants. 



Leaves dissected. CERATOPHYLLACEAE, 150. 



Leaves entire. CALLITRICHACEAE, 237. 



Terrestial plants; flower-clusters surrounded by a petaloid involucre; 

 ovary 3-celled, raised above the Staminate flowers; the whole appear- 

 ing as a single flower. EDPHORBIACEAE, 231. 



