SUB-CLASS III. COROLLIFLORJE. 487 



and bitter ; and the leaves and roots of many species act as 

 purgatives, and even emetics. These qualities are united in the 

 Foxglove (which approaches in many of its characters to the 

 Solanese), with a remarkable power of depressing the nervous 

 system, and of diminishing the action of the heart; and, when 

 cautiously administered, this is a medicine of great value. 



663. The following table will enable the student to distin_ 

 guish such of the orders of this sub-class, as he is likely to meet 

 with among British Plants. Here, as elsewhere, it is to be 

 remarked, that such tabular arrangements, being founded upon 

 such single characters only as are easily recognized, do not at all 

 represent the real affinities or relationships between the orders. 



SUB-CLASS III. -COROLLIFLOILE. 



Monopetalous Exogens, having a superior ovary, and the 

 stamens inserted on the corolla. 



A. Flowers regular, stamens of equal length. 



a, Ovary 4-lobed externally . Borayineae, 655 



&, Ovary undivided, 

 a, Carpels 4 or 5. 



Stamens opposite petals, . . Primulacete, 645 

 Stamens alternating with petals, . Convolvulacece, 651 

 , Carpels only 2. 



Stamens 2 ... Oleacece, 647 



Stamens 4 or more. 



Calyx imbricated . . . ConyolvulacetB* 



Calyx in a perfect whorl. 



Leaves opposite . . Gentianeee, 650 



Leaves alternate . . Sotanece, 656 



B. Flowers irregular, stamens usually tetrady- 



namous. 



a, Ovary 4-lobed externally . . Labiate, 654 



b, Ovary undivided. 



a, Stems leafy, not parasitic, capsule two- 

 celled .... Scrophularineee , 660 



8, Stems leafless, habits parasitic, capsule 



one-celled . . . . Orobanchea, 660 



* This order is repeated here, because several of its species, as the Dodders, 

 have less than four carpels developed in the ovary. 



