EXOGENOUS OE DICOTYLEDONOUS PLANTS. 429 



Group 2. Ovary coherent with the calyx, one-celled and one-ovuled, or rarely 

 3-colled with two of the colls empty, and the third one-ovuled. Seed with 

 little or no albumen. Stamens inserted on the corolla. Limb of the ca- 

 lyx a mere ring, crown, or pappus, or none. Stipules none. 



Stamens distinct. Seed suspended. Leaves opposite. Stamens 3, or rarely 2. 



Flowers often irregular. Valerianace^. 



Stamens 4. Flowers regular, in an involncrate head. Dipsace^e. 



Stamens syngenesious. Seed erect. Composite. 



Group 3. Ovary coherent with the calyx, with two or more cells and numer- 

 ous ovules. Seeds albuminous. Stamens inserted with the corolla (epi- 

 gynous) : anthers not opening by pores. Juice more or less milky. 



Corolla irregular. Stamens united by their anthers or filaments. Lobeli ace^. 

 Corolla regular. Stamens distinct. Campan0laceje. 



Group 4. Ovary free from the calyx, or sometimes coherent with it, with two 

 or more cells and few or many ovules. Seeds albuminous. Stamens in- 

 serted with the corolla, or rarely somewhat coherent with its base, as many, 

 or twice as many, as its lobes : anthers mostly oijening by pores or 

 chinks. Eeicace.S). 



Group 5. Ovary free, or rarely coherent with the calyx, several-celled, with a 

 single ovule (or at least a single seed) in each cell. Seeds mostly albu- 

 minous. Stamens definite, as many as the lobes of the (often almost poly- 

 petalous) corolla and alternate with them, or two to four times as many: 

 anthers not opening by pores. — Trees or shrabs. 



Stamens as many as the lobes of the corolla : no sterile ones. Aquifoliace.^. 

 Stamens more numerous than the lobes of the corolla, and all fertile. 



Flowers polygamous : calyx free. Ebenace^. 



Flowers perfect : calyx more or less adnate. Styracace^. 



Stamens as many fertile as the lobes of the corolla and opposite 



them. SAPOTACEiE. 



Gi'oup 6. Ovary free, or with the base merely coherent with the tube of the 



calyx, one-colled, with a free central placenta. Stamens inserted into the 



regular corolla opposite its lobes ! which they equal in number. Seeds 



albuminous. 



Shi-ubs or trees (all tropioal) : fruit drupaceous. Mtrsinace.-e, 



Herbs : fruit capsular. Peijiulaoe^. 



Group 7. Ovary free, one-celled, with a single ovule ; or two-celled with 

 several ovules attached to a thick central placenta. Stamens as many as 

 the lobes of the regular corolla or the nearly distinct petals. Seeds albu- 

 minous. 



Ovary two-celled : style single : stamens 4, or rarely less. Plantaginace^. 

 Ovary one-celled : styles and stamens 5. Plumeaginace^. 



Group 8. Ovary free, or rarely partlj' coherent, one- or two- (or spuriously 



