412 SYSTEMATIC BOTANY, OR 



similar to the first thirteen Classes. The number of stamens 

 is, however, never less than three. Thus :— 



Order 1. Triandria, with three stamens, as in Tamarind, &c. 

 Order 2. Pentundria, with five stamens, as in Erodium, Passi- 



flora. 

 Order 3. Hexandria, with six stamens, as in Fumitory. 

 Order 4. Heptandria, with seven stamens, as in Pelargonium. 

 Order 5. Octandria, with eight stamens, as in Poli/guh. 

 Order 6. Decandria, with ten stamens, as in the Pea, Vetch, 



and many other Papilionaceous flowers. 

 Order 7. Dodecandria, with twelve to nineteen stamens, as in 



the Orange, &c. 

 Order 8. Pob/andiia, with twenty or more stamens, as in the 



Mallow, St John's-wort, &c. 



In the 19th Class, Si/ngene.sio, we have five orders. The 

 flowers in all are compound. By Linnaius a sixth order was in- 

 cluded in this class, under the name of Monogamia, which em- 

 braced all solitary flowers tliat had united anthers, as Lobelia, 

 Violet, &c.; but this order was afterwards abolished, so tliatthe 

 class Syngenesia, as it now stands, is essentially a natural one, 

 and corresponds to the order Composite of the Natm-al Systems. 

 The names and characters of the orders are as follows: — 



Order 1. Polygamia cequalis. This includes all plants in which 

 the flowers or florets of the capitula are all perfect 

 or hermaphrodite, as in Lettuce. Cliicory, Dan- 

 delion, &c. 



Order 2. Polygamia superflua, where the florets of the disk or 

 centre of the capitula are hermaphrodite, and those 

 of the ray or of the margin are pistillate, as in the 

 Daisy, Elecampane, Chamomile, &c. 



Order 3. Polygamia frustrajiea, where the florets of the disk are 

 hermaphrodite, while those of the ray arc neuter, 

 as in Centanrea, the only British genus which 

 presents this structure. 



Order 4, Polygamia necessaria, where the florets of the disk 

 are staminate and sterile, while those of the ray 

 arc ])istillate and fertile, as in the Marigold (^Calen- 

 didii). 



Order 5. Polygamia segregata, wliere each flower or floret of the 

 capitulum has an involucre of its own, as in the 

 (Jlobc-thistle (Er/iinops). The last two orders do 

 not include any British Plants. 



The Orders in tlic 20th, 21st, and 22nd Classes, arc founded 

 on the number and union of the stamens; as such characters 



