268 BOTANICAL INTRODUCTION. 
er than the other two. Pepper, radish, and mustard, are in 
this class. 
15th class. Monadelphia or one brotherhood; in this class 
we include all such plants as have their filaments united into 
one ser. The fifth order of this class contains the genus pas- 
siflora or passion-flower; the seventh order contains pelar¬ 
gonium, and includes the genus geranium ; the thirteenth ordet 
malvacae, includes those flowers whose stamens'are united in 
a column, as the hollyhock, camellia japonica, mallow, and 
cotton. 
16th class. Diadelphia, two brotherhoods; this class includes 
all those flowers which .have their filaments united into two 
sets. The flowers of this class are called papilionaceous or 
butterfly-shape, as the bean and the pea. WTien these flowers 
contain ten separate stamens, even if papilionaceous, it is 
placed in the 10th class, Decandria. But this is a point diffi¬ 
cult to ascertain, as in the pea for instance, it is necessary to 
take a pin and separate the filament which is alone, in order to 
perceive that it is not united to the other nine. This class con¬ 
tains the fumaria, Seneca snakeroot, and the whole family of 
plants with leguminous pods. 
17th class. Syngenesia; this comprises a great number of 
plants. The essential marks of this class consist in the union 
of anthers j this gives a compound character to the flowers, 
making each plant a collection of little florets, placed upon 
the same receptacle, and within one common calyx; add to this 
the five stamens with their anthers united, forming a little 
tube. This class includes the marigold, the genus artemisia, 
the family of the asters, solidago or golden rod, and the genus 
chrysanthemum. 
18th class. Gynandria. This presents an entirely new fea¬ 
ture, which is the situation of the stamens upon the pistil, 
since the stamens appear to proceed from that organ. In this 
