10 Principles of Classification* 
in mallow and Iavatera, and less obvious in the mime® 
rous family of geranium. 
The 17th class, Diadelphia, has the stamens united 
by their filaments in two parcels ; and it is a natural 
class, for it consists of papilionaceous flowers, of which 
the flowers of th<| pea tribe are examples. 
The 18th class , Poly adelphia^ includes such plants as 
have the stamens united by the filaments into more 
than two parcels, as in St Johnswort. 
In the 19th class, Syngenesia , the stamens are unit- 
ed by their anthers into a tube, and the flowers of this 
class are compound, that is, a number of flowers is-col» 
lected together within the same calyx, or upon the same 
receptacle, of which the common daisy, dandelion, and 
sun-flower furnish appropriate examples. 
The 20th class, Gynandria, is characterised by the 
stamens growing out of the pistil, or being united with 
it, of which examples are found in the orchis tribe. 
The 21st class, Moncecia, signifying one house, inclu*» 
des those plants which have stamens and pistils in sepa- 
rate flowers, but growing on the same plant, as in the 
dak and hazel. 
In the 2 2d class, Dicecia , which signifies two hou- 
ses, the stamens and pistils are not only in separate 
flowers, but the flowers which produce stamens, and 
those which produce pistils, grow on separate plants, 
as in the hop, the willow, and yew. 
The 23d class, Polygamia t comprehends such plants 
as have stamens and pistils separate in some flowers and 
united in others, either, on the same plant or on two or 
three different plants, as in pellitory, and sea-purslane. 
The 24th class, Crypiogamia , includes those plants 
in which the parts of fructification are not distinctly 
