INTRODUCTION. 
ix 
15. 
Tetradynamia. Stamina 6. 
four long and t^o short. 
contained in a seed vessel ; and here again we have 
natural characters distinguishing between noxious 
and innoxious plants. In the 1st order with the 
naked seeds, the plants are mostly aromatic and 
wholesome, including Mentha, La^^ndula, &c. In 
the 2d order, where the seeds are enclosed in a seed- 
vessel we have the Digitalis and other poisonous 
plants. 
This class is likewise easily distinguishable from 
the 6th class, Hexandria. The flowers of this class 
are all cruciform, and consist of 4 petals. It is 
divided into two orders, Siliculosa, with short round 
pods, and Siliquosa, with long pods. In this last 
order of the class, we have the dilferent species of 
Brassica, or cabbage, Sinapis, &c. 
10. MoNADELPHIA. Stamina There are eight orders in this class, distinguished 
more or less numerous by the number of tlieir stamens. The Malva and 
tinited by their fila- Althaea are illustrations of this class, 
ments into one tube. 
17. DiADELPHiA. Stamina This is a very distinct class, consisting of papilio- 
unitedinto two parcels naceous flowers. The orders are distinguished as ia 
at the base. the preceding class. The Astragalus Tragacantha 
belongs to this class. More familiar specimens of it 
will be found in the garden pea, betm, and other 
leguminous plants. 
18. PotyADELPHlA. Stamina 
united into more than 
two parcels. 
19. Syngenesia. Anthers 
united into a tube; the 
flowers compound. 
20. Gynandria. Stamina 
united with, or grow- 
ing out of the pistil, 
and either proceeding 
from the germen or the 
style. 
21, MoNfficiA. Stamina 
and Pistils, in separate 
VOL, I. 
The orders of this class have not been very well 
defined by Linnaeus. The class contains the citrus 
tribe of fruits. 
This class consists of 5 orders. 1st — Polygamia 
iEqualis, where each floret is perfect, being fur- 
nished with stamens and pistils, and capable of 
bringing its seed to maturity. The Leontodon will 
illustrate this or3er of the class. 2d — Polygamia 
Superflua. The florets of the disk perfect, those of 
the margin having pistils only, but both perfecting 
their seed. The Artemisia is an example of this 
order, but a better one will be furnished in the An- 
themis Nobilis of the fields. 3d — Polygamia Frus- 
tanea. Florets of the disk perfect or united, those 
of the margin neuter, or destitute of pistils as well as 
of stamens. This order is by no means well defined, 
and might with great propriety be abolished. 4th— 
Polygamia Necessaria. Florets of the disk fur- 
nished with stamens only, those of the radius only 
with pistils, and both being necessary for the per- 
fecting of the seed. The Calendula, or garden 
marygold, is a familiar specimen of this order, 
5th — Polygamia Segregata. Several flowers, either 
simple or compound, with united tubular anthers, and 
with a partial calyx, all included in one common or 
general calyx. The globe thistle illustrates this 
order. 
The orders of this class are taken from the number 
of the pistils, but botanists are not agreed as to the 
admission of some of them into the class. The 
Aristolochia belongs to the class Gynandiia. 
The orders in this class depend upon the circum- 
stances of their male flowers, and are 9 w 10 iu uum- 
C 
