18S 
CLASS GYNANDRIA. 
Orchis tribe of Plants. 
The natural order, Orchidese, is composed of genera which be- 
long to- the class Gynandria ; the principal of these is the Orchis 
genus, the different species of which are mostly perennial, and grow 
in moist and shady places ; some are parasites, adhering to the bark 
of trees by their fleshy, fibrous roots. The roots sometimes con- 
sist of two solid bulbs, in other cases, they are oblong, fleshy sub- 
stances, tapering towards the ends like the fingers of the hand. The 
name Orchis is derived from a Greek word, signifying an olive-ber- 
ry, on account of the root being round, like that fruit. The distin- 
guishing characters of this tribe, are a corolla, above the germ, 5 
petals, 3 external and 2 internal. There is also in each corolla, a 
petal-hke organ called the hp, which varies in form and direction; 
anthers always 1 or 2, and from 1 to 4-celled, sessile, or sitting upon 
the side or apex of the style ; the pollen is easily removed from the 
cells in glutinous masses ; the styles are simple, with viscous stigmas 
of various forms and positions. The capsules are l-celled, 3-valved, 
3-keeled ; the seeds are numerous and dust-like, the leaves clasp the 
stem like the leaves of grasses. The stems or scapes are simple, 
and the flowers are arranged in spikes or racemes. 
This natural order has monocotyledonous seeds, and stamens epi- 
gynous, or above the germ. The flowers are remarkable for their 
irregular, and we might add, grotesque appearance ; some present 
the figure of a fly, others of a spider, a bird, and even of the 
human figure. It would seem too that the freaks of these vegeta- 
ble beings are not designed for our observation, for they are .as 
peculiar in their choice of habitations as in their external forms, 
preferring wildness, barrenness, and desolation to the fostering care 
of man, or the most luxuriant soil. It is in forests of the equatorial 
regions, that these plants appear in the greatest perfection. The 
aromatic vanilla is obtained from the fruit of a climbing orchis of 
those regions. 
The Orchis genus has a nectary in the shape of a horn ; its co- 
rolla is somewhat ringent, the upper petal vaulted, the lip is spread- 
ing, the 2 masses of pollen are concealed at the sides, by little sacs, 
or hooded hollows of the stigma. 
Fig. 146 represents a flower of this genus ; a, shows the two 
masses of pohen, brought out from the cells of the anther, which is 
attached to the pistil. 
Order Diandria 
The 2d order contains the ladies' slipper, (Cypripedium ;) the nec- 
tary or lip is large, inflated, and resembles a shpper. We have 
several species of this curious plant, some of which are yellow, 
some white, and others purple. 
Order Pentandria. 
The 5th order contains the milk- weed, (Asclepias ;) this by some • 
botanists is placed in the fifth class, on the supposition that the sta- 
mens do not proceed from the pistil. 
Order Hexandria. 
The 6th order contains the Virginia snake-root, (Aristoloohia 
serpentaria,) a perennial plant, with brown fibrous roots ; it is found 
in shady woods, from New-England to Florida : the root is highly- 
valued in medicine; it possesses an aromatic smell, somewhat simi- 
lar to spruce. It is said to have been found, by a chemical analysis, 
Natural order Orchidens— Distinguishing characters of this family — Orchis — Ordor 
Diandria— Order Pentandria— Order Hexandria— Virginia snake-root. 
