SEED. 
99 
nous seeds, as the bean, orange, and apple, the embryo may be 
plainly discovered. Its internal structure, before it begins to vege¬ 
tate, is very simple, consisting of a uniform substance, enclosed in'its 
appropriate bark or skin. When the vital principle is excited to 
action, vessels are formed and parts developed which were before 
invisible. The embryo is usually central and enclosed by the coty¬ 
ledons ; sometimes it is no more than a mere point or dot, and in 
some cases, altogether invisible to the naked eye. 
The embryo consists of the plume and radicle. 
The Plume , or plumula, which is the ascending part, unfolds itself 
into herbage. 
The Radicle , or descending part, unfolds it¬ 
self into roots. At Fig. Ill appears the 
embryo in a germinating state ; a, represents 
the radicle, h, the plume, c, the funicle, by 
means of which the plant is still connected to 
the cotyledons, and receives from them its 
nourishment. 
To use the words of an ancient botanist, 
“ the, embryo continues imprisoned within its 
seed, and remains in a profound sleep, until 
awakened by germination, it meets the light 
and air, to grow into a plant, similar to its 
parent.” 
“ Lo S on each seed, within its slender rind, 
Life’s golden threads in endless circles wind ; 
Maze within maze the lucid v/ebs are roll’d, 
And as they burst, the living flame unfold* 
The pulpy acorn, ere it- swells, contains _ 
The oak’s vast branches in its milky veins, 
Each ravell’d bud, fine film, and fibre-line, 
Traced with nice pencil on the small design. 
The young Narcissus, in its bulb compressed, 
Cradles a second nestling on its breast; 
In whose fine arms a younger embryo liea^- 
Folds its thin leaves, and shuts its floret-eyes; 
Grain within grain, successive harvests dwell, 
And boundless forests slumber in a shell.”* 
i 
There are various appendages which may or may not be present 
without injury to the structure of the seed. 
Aigrette , or egret , sometimes called pappus, is a kind of feathery 
crown with which many of the compound flowers are furnished, 
evidently for the purpose of disseminating the seed to a considerable 
distance, by means of winds ; as the dandelion* It includes all that 
remains on the top of the seed after the corolla is removed. 
Stipe , is a thread connecting the egret with the seed. The egret 
is said to be sessile , when it has no stipe, simple wdien it consists 
* These lines, which so beautifully set forth the manner in which the embryo is 
contained within the seed or bulb, are not strictly philosophical, as to the fact of the 
future generations lying enfolded, the one within the other; it is true, that we may in 
many seeds, by the help of a microscope, discern the form of the future plant, but we 
cannot believe that this is the miniature image of another plant, which contains an¬ 
other, and so on through successive generations; for the fact is established, that a 
seed does not produce a plant without being fertilized by the pollen. We may say that 
a seed contains within itself the elements of future generations; but not their images , 
except that of the immediate plant which is to issue from the perfected seed. 
* What are the parts of the embryo ?—Plume—Radicle—What is the egret ?—Stipe 7 
