DIADELPHIA. 341 



3. Octandria. Polygala, t, 76, is the principal genus 

 here. America and the Cape of Good Hope abound 

 in beautiful species of it, and New Holland affords 

 some new genera, long confounded with this. Dal- 

 bergia is perhaps as well placed in the next Order. 



4. Decandria is by far the most numerous, as well as 

 natural, Order of this Class, consequently the genera 

 are difficult to characterize. They compose the fam- 

 ily of proper Papilionac<£ ov Leguminosce^ the Pea, 

 Vetch, Broom, &c. Their stamens are most usually 

 9 in one set, with a single one separate. 



The genera are arranged in sections variously charac- 

 terized. 



* Stamens all united, that is, all in one set. The 

 plants of this section are really not diadelphous but 7720- 

 nadelphous. See Spartium, Engl. Bot. t. 1339. Some 

 of them, as Lupinus, and Vlex, t. 742, 743, have in- 

 deed the tenth stamen evidently distinguished from the 

 rest, though incorporated with them by its lower part. 

 Others have a longitudinal slit in the upper side of the 

 tube, or the latter easily separates there, as Ononis, t. 

 682, without any indication of a separate stamen. Here 

 therefore the Linnasan System swerves from its strict 

 artificial laws, in compliance with the decisive natural 

 character which marks the plants in question. We ea- 

 sily perceive that character, and have only to ascertain 

 whether any papilionaceous plant we may have to ex- 

 amine has 10 stamens, all alike separate and distinct, in 

 which case it belongs to the 10th Class, or whether they 

 arc in any way combined, which refers it to the 17ih. 



