KEY TO THE ORDERS. xxi 



Ukticacb,*;. — Herbs. Stigma 1. Flowers monoecious or 

 dioecious, m spikes or racemes. No chaff-like bracts 

 among the flowers. Or, Stigmas 2 ; leaves pal- 

 uiately-compouud 198 



Illeoebrace^. — Herbs, small, tufted. Flowers greenish 

 or whitislj, terminal. Stamens as many as the 

 divisions of the 5-parted calyx and opposite them, 

 or fewer, perigynous. Sepals hooded at the top 

 and bristle-pointed. Style 2-oleft. 183 



AMjVBAKtace^. — Herbs. Flowers greenish or reddish, in 



s^ik.ea,with chaff-likebracts interspersed. Stigmas 2. 187 



Chenopodiace^e. — Herbs. Flowers greenish, in spikes. 



No cha^-like bracts. Stigmas 2 ISi 



OLEACE.E. — Trees. Leaves pinnalely compound. Fruit a 1- 



seeded samara 181 



Urticace.e. — Trees. Leaves simple. Fruit a 1 -seeded sa- 

 mara winged all round, or a drupe 198 



Laitkace.e — Trees of shrubs. Flowers dioecious. Sepals 6, 



petal-like. Stamens 9, opening by uplifting valves. 1 93 



TuYMELEAOE^. — Shrubs with leather-like bark, and jointed 

 branclilets. Flowers perfect, preceding the leaves. 

 Style thread-like 194 



K. Flowers i» catkins. 



* Steri'e pr staminate flowers only in catkins. 



JuGLANDACE.E. — Trees with pinnate leaves. Fruit a nut 



with a husk 202 



Cdpulifer,e. — Trees v^ith simple leaves. Fruit one or 

 more nuts surrounded by an involucre which 

 forms a scaly cup or bur 204 



f * Both sterile or fertile flowers in ccctkins, or cathin-like heads. 



SAbiCACE.n. — Shrubs or low trees. Ovary l-celled, many- 

 seeded ; seeds tufted with down at one end 2U9 



Plaianace.e. — Large trees. Stipules sheathing the hranjih- 



lets. Tlie flowers in heads ... 201 



Myric.vck.e. — Shrubs with resinous-dotted, usually fra- 

 grant, leaves. Fertile flowers one under each 

 scale. Nutlets usually coated with waxy grains. . 203 



BETULACE.E. — Treos or shrubs. Fertile flowers 2 or 3 under 

 each scale of the catkin. Stigmas 2, long and 

 slender , 207 



