CLASS POLYANDRIA. 
this division proper. In this tribe, the most important genus is Py= 
rus, which contains the apple and pear. The varieties of these fruits 
are the effects of cultivation, not the produce of different species. 
By means of grafting, or inoculation, good fruit ma}^ be produced 
upon a tree which before produced a poorer kind. 
> Jussieu divided his natural order Rosaceee into the following sec¬ 
tions ; the PomacecBj with fruit fleshy, like the apple and pear; the 
Rose?., having urn-form calyxes; Amygdalae , having drupe-like fruits. 
Order Polygyria. 
The rose tribe ( Rosaceee ) resemble the apple tribe, in the appear¬ 
ance of the blossom, but the fruit, instead of being a Pome, consists, 
either of nuts containing one-seeded acines, as the rose, or of ber¬ 
ries, as the strawberry. " The leaves have two stipules at their base. 
The rose unchanged by cultivation has but five petals. We have 
few indigenous species of this genus; among these, are the small 
wild rose, the sweet brier, and swamp rose. Red and white roses 
are remarkable in English history as emblems of the houses of 
York and Lancaster ; when those families contended for the crown, 
in the reign of Henry the Sixth, the white rose distinguished the par¬ 
tisans of the house of York, and. the red those of Lancaster. 
Among the nations of the East, particularly in Persia, the rose flour¬ 
ishes in great beauty and is highly valued. The Persians poetically 
imagine a peculiar sympathy between the rose and the nightingale. 
The Blackberry ( Rubus ) has a flower resembling the rose in 
general aspect; there are several species of the Rubus, one which 
produces the common blackberry, another the red raspberry, another 
the black raspberry, and another the dewberry. One species, the 
odoratus , produces large and beautiful red flowers, the fruit of which 
is dry and not eatable. 
The Strawberry belongs to the same natural and artificial order as 
the Rose. The gathering of strawberries in the fields, is among the 
rural enjoyments of children, which in after life are recollected with 
pleasure, not unfrequently mingled with melancholy reflections, upon 
the contrast of that happy season, with the sorrows with which 
maturer years are often shaded. The fruit of the strawberry, as was 
remarked in the classification of fruits, is not properly a berry, but 
a collection of seeds, imbedded in a fleshy receptacle. 
Icosandria furnishes us with a great variety of fine fruits, more 
perhaps than any other of the artificial classes. A great proportion 
of the genera to be found in this class, are natives of the United 
States. 
LECTURE XXXI. 
CLASS XII.—POLYANDRIA. 
In this class we find the stamens separate from the calyx, and at¬ 
tached to the receptacle or top of the flower-stem. The number of 
stamens varies from twenty to some hundreds. This class does not, 
like the one we have last examined, contain many delicious fruits, 
but abounds in poisonous and active vegetables. The mode of in¬ 
sertion of the stamens is to be regarded in considering the wholesome 
Order Pomaceee—Pyrus, varieties by grafting—Order Rosaceae divided into sections 
—Rose tribe—Blackberry—Strawberry—Class Polyandria. 
