202 GARDENING AS A SCIENCE. 
" The seed is wrapped in a small leaf, which, instead of expanding its beauties 
to the sun and air, like its neighbouring petals, folds itself closely round the little 
treasure it is to protect : the edges of the two opposite leaves of the leaf being 
thus brought in contact, unite and grow together^ and the leaf assumes the form of 
a pod or vessel, the shape of which varies according to, the form of the leaf, and 
the manner in which it was folded when it first budded." 
Again : " When this leaf is closed over the seed, and its edges soldered together, 
it is called an omry or seed-vessel. From its summit rises a little thread-like 
stalk, called a style^ which at its extremity supports a small spongy substance 
denominated stigma. These three parts form a whole, which bears the name of 
Carpel." 
The simple facts concerning the structure of the pistil in the above extract, are 
plain and elucidatory ; the value of the flowery illustration of the true Morpheo- 
logical Theory will speak for itself. That the pod of a bean, pea, or other species 
of the leguminous tribe is nothing more than a /^o/* glued or soldered together at 
its edges, is somewhat startling ; we therefore leave the hypothesis to its own 
merits. 
The pistil being the central organ of the flower, and the envelope of the seeds, 
is surrounded, more or less, by the stamens in such plants as have both in the same 
flower ; for there are many, wherein the stamens and pistil are apart, and even in 
different plants. The structure of a stamen usually comprises a slender filament, 
at the summit of which is attached, in various ways, a little cellular organ (filled 
with small vesicles) called the anther. As the vesicles ripen, they become the fine 
dust or pollen, botanically termed Farina. 
Each granule of farina is cavernous ; and at the period of perfect maturity, 
it explodes when it comes in contact with the moist surface of the stigma, a fact 
which appears to be corroborated by microscopic investigation. Upon this fact 
are founded the theory and practice of impregnation. 
There are many difiiculties attendant upon the theory ; and these are increased 
by the known circumstance, that the male and female organs of the same plant 
are, in numerous instances, entirely separate ; in others, wherein both organs exist 
in the same flower, yet the anthers cannot come in contact with the pistillum. 
As, however, artificial impregnation is now extensively resorted to, in order to 
produce new varieties, we must be content to believe that which is highly probable, 
and thus sanction the partial analogy that appears to exist between the animal 
and vegetable creation. 
If we admit the theory of impregnation of seeds by the agency of the " farina 
fructicans," it is essential to inquire minutely into the laws which govern this 
wonderful process, and the limits to which they extend. The following paragraph 
from the article Impregnation" of the Cyclopaedia of the Society for the 
Diffusion of Useful Knowledge, will be read with interest : — " In a perfect 
plant, the anther or male organ contains a matter called pollen. The pollen is a 
