KEY TO THE ORDERS. 



Ovules, and seeds, boi-ne on the face of a bract or a scale : stigmas wanting. 



Class 1. Gymnospermab. 

 Ovules, and seeds, in a closed cavity (ovary) : stigmas present. 



Class 2. Angiospersiae. 



1. Gymnospermae. 



Plants growing by lateral as well as by terminal buds, with scale-like, flat or needle- 

 like leaves not circinate : embryo not prolonged into a spiral. Order Pixales. 



2. Angiospermae. 



Cotyledon 1 : stem endogenous. Subclass 1. Moxocotyledonbs. 



Cotyledons normally 2: stem exogenous (with rare exceptions). 



Subclass 2. Dicotyledones. 



1. Monocotyledones. 



Leaf-blades pinnately or palmately lobed, or compound : ovules solitary in each 

 carpel-cavity. Order Arec.\.les. 



Leaf-blades narrow, entire or essentially so, simple : ovules many 



in each carpel-cavity. Order Liliales. 



2. Dicotyledones. 



A. Corolla wanting, except in the pistillate flowers of Juglans (Juglandaceae). 

 Calyx wanting, at least in the staminate flowers, except sometimes in Castiarina 

 (Casuarinaceae). 

 Leaves represented by appressed whorled scales : stems or branches loosely 

 jointed. Order Casuakixales. 



Leaves not appressed scales : stems or branches not loosely jointed. 

 Fruit 1-seeded : seeds without tufts of hairs. 



Pistillate flowers without a calyx : ovule erect and orthotropous. 



Order Myricales. 

 Pistillate flowers with a calyx : ovule pendulous and anatropous. 



Leaf-blades simple. Oleaceae in Order Oleales. 



Leaf-blades compound : fruit a samara. Oleaceae in Order Oleales. 

 Fruit many-seeded : seeds each with a tuft of hairs. Order Salicales. 



Calyx present at least in the staminate or in the perfect flowers. 



Leaves represented by appressed whorled scales : branches loosely jointed. 



Order (IJasuarixales. 

 Leaves not appressed scales : branches not loosely jointed. 



Flowers, at least the staminate, in aments, or ament-like spikes. 



Pistillate flowers separate at maturity : fruit a nut or an achene. 



Order Fagales. 

 Pistillate flowers forming an aggregate fruit : fruits drupe-like. 



Artocarpaceae in Order Ubticales. 

 Flowers at least the staminate, not in aments. 

 a. Ovary superior. 



Gynoecium of 1 or several and distinct carpels : stigma and style 

 solitary. 

 Carpel solitary. 



Stamens borne under the gynoecium. 



Pisoniaceae in Order Chenopodiales. 

 Stamens borne on the hypanthium or adnate to the calyx- 

 tube. Order Tiiymeleales. 

 Carpels several. Families in Order Raxales. 

 Gynoecium of 2 or several united carpels : stigmas or styles 2 or 

 several. 

 * Ovary, by abortion, 1-celled and 1-ovuled. 

 Leaves with sheathing stipules (ocreae). 



Order Polygoxales. 

 Leaves estipulate. or if stipules are present they are not 

 sheathing. 

 Trees. 



Anthers opening by slits : ovary not seated in a 

 hypanthium. Ulmaceae in Order Urticales. 



Anthers opening by hinged valves : ovary seated in 

 an accrescent hypanthium. 



I^auraceae in Order Tiiymeleales. 

 Vines. Order Chexopodi-vles. 



