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ON THE STUDY OF THE SCIENCE OF BOTANY. 
and use as an article of food, are found in this class. The Geranium, 
Camellia, and Passijlora, are also genera of much beauty, the latter 
yielding some delicious fruits. The characters of this are, 
1. Calyx, a perianthium always present, persisting, and in some 
genera double. 
2. Corolla pentapetalous, heart-shaped, the sides of which lap each 
ne over the next, contrary to the motion of the sun. 
3. Stamina, the filaments united below, but distinct upwards; the 
exterior ones shorter than the interior. The anthers incumbent. 
4. Pistillum, the receptacle of the fructification, prominent in the 
centre of the flower ; the germen erect, surrounding the top of the recep¬ 
tacle in a jointed ring ; the styles are all united below in one substance 
with the receptacle, but divided above into as many threads as there 
are germins; the stigma spreading and thin. 
5. Pericarpium, a capsule divided into as many loculaments as there 
are pistilla. 
6. Semina, reniform, or kidney-shaped. 
The orders of this class, which are seven in number, are derived 
>. 
from the number of stamens, the styles being now discarded from 
distinction. Orders seven, viz. : 
Triandria ; Tigridia pavonia. 
Pentandria ; Hermannia jlamea. 
Heptandria; Pelargonium tricolor. 
Octandria ; Ailonia capensis. 
Decandria ; Geranium Wallachianum . 
Dodecandria ; Pentapetes ovata. 
Polyandria ; Camellia japonica. 
Classis XVII.—Diadelfhia. 
Diadelphia, taken from dis, 
two, adelphos, a brother, or 
brotherhood, meaning that this 
class is furnished with bisex¬ 
ual flowers, having their stamens 
united into two bodies. With regard to the importance of dia- 
delphous plants, as applicable to the purposes of mankind, they may 
be said to hold the very highest rank. All the numerous varieties of 
pulse, whether eaten by men or cattle, as peas, beans, haricots, cara- 
vances, lentils, and others, are all produced from plants of this class. 
The best of our artificial grasses, such as clover, lucerne, saintfoin, &c.. 
