4i6 _ The Ohio Naturalist. [Vol. XII, No. 2, 



MYRTIFLORAE. 



Epigynous plants usually with large showy flowers, with or 

 without a prominent hypanthium; more commonly chorijjetalous, 

 but sometimes sympetalous or completely apetalous; ovules 

 commonl}- ntunerous. 



Synopsis. 

 I. Fleshy usually prickly and spiny plants with jointed stems and 

 reduced leaves; perianth segments usually very numerous. 



Cactales. 

 II. Herbs, shruljs or trees not spiny like the preceding; calyx- 

 segments rarely more than 5. 



1. Petals usually present, choripetalous ; sometimes apetalous 



or sympetalous. 



a. Flowers usually bisporangiate, placentae usually axile 



or apical, rarely basal. Myrtales. 



b. Flowers bisporangiate or monosporangiate; placentae 



usually parietal; mostly herbs or herbaceous vines. 



Loasales. 



2. Petals usually absent; if present either choripetalous or 

 sympetalous. 



a. Ovulary with several ca^^ities, usualh" 6-locular; 



herbs or vines. Aristolochiales. 



b. Ovulary unilocular; mostly parasitic herbs or shrubs. 



Santalales. 



HETEROMERAE. 



Low, often evergreen, shrubs, trees, or herbs usually with 

 hypogynous flowers which are usually sympetalous but sometimes 

 choripetalous; perianth usually regular or nearly so inserted on 

 the floral axis; stamens united with the corolla or free, usually as 

 many or twice as many as the corolla-lobes; carpels usually 5-3. 



Synopsis. 



I. Ovulary mostly unilocular and usually with a free central 

 placenta; stamens opposite the petals or more ntunerous, 

 united with the corolla, mostly herbs. Primulales. 

 II. Ovulary mostly 2-or more locular or with parietal placentae; 

 herbs, shrubs, or trees. 



1. Stamens mostly free from the corolla, alternate with its 



lobes or twice as many; seeds minute; flowers bispo- 

 rangiate, hypogynous, sometimes choripetalous. Ericales. 



2. Stamens united with the corolla, opposite its lobes or 



twice as many or more; seeds usually solitary or few, 

 usually large; flowers hypogynous or sometimes epi- 

 gynous, sometimes choripetalous. Ebenales. 



