No, they are not: though Compound flowers are made up of sets of
flowers within the same calyx, we have plants in which the stamen,
or male flowers, are in one part, and the pistil, or female flowers,
on another portion of the tree. The former are barren flowers; the
latter, fertile or fruitful, as the seed vessel is only connected with
the female side.
I think the service of winds, insects, and birds, is more needful
than ever now. But I have seen people pick off flowers from melon and
cucumber plants, saying, that they were no good.
These were the male blossoms. But they who pluck off all the barren
blossoms before the pollen appears, can never expect to have fruit; for
the fertile blossoms are of no use without the others. But what would
you think of male flowers being all on one tree, while the female are
upon another at a distance?
I suppose that is to give the birds and insects more work than ever.
Please tell me a tree that has this curious plan.
The Palm is an instance. Where the trees grow in a cluster, as they
usually do, there is no difficulty. If very far apart, the male
blossoms, when ripe, are cut off, carried to the other tree, and the
pollen shaken over the pistil flowers.
That is singular. But how do water plants get on with the yellow dust?
Some of them rise to the surface to flower, and sink to seed. Those
that keep below are provided with a glutinous pollen, which cannot be
affected with the wet.
* * * * *
Well, father, I do think we are getting on bravely with our lesson. But
I would so like to peep into the germen or ovary, and see what goes on
there.
We will do so. I ought to have said, that before the pollen sheds, the
ovary has a lot of half formed seeds adhering to the _Placenta_ inside.
These _Ovules_, as they are called, are a sort of nucleus or kernel,
and are each placed between two sacs of open mouths.
What goes into those mouths?
Nothing goes in, but the pollen of the stamens comes down through them
out upon the ovule, and is received to its _Embryo_, or heart, through
a very small hole. Soon after the pollen has entered, the ovule becomes
perfected and vivified, or made full of life.
And is that the seed?
The ovules do then become seeds in their little cells, and are, in
their turn, shed out when ripe.
But do they turn into real seeds directly the pollen gets down?
By no means. Nourishment and time are necessary to growth and change.
I must explain further about the seed. Beneath the _integument_ or
covering of ordinary seeds, as a pea, what do you observe, Willie?
I have seen the two halves of the seed show themselves, when the skin
breaks, and the plant seems to grow from between them.
Your two halves are the _lobes_ or _cotyledons_ of the seed. These
fleshy substances enclose the _embryo_, from which the leaves and
roots proceed. The upper part, from which the leaves arise, is the
_Plumula_, or _little plume_, or feather. That from which the rootlet
proceeds is the _Radicle_, or root part: sometimes it is called the
_Rostellum_, or _little beak_.
Of what use are the cotyledons, father?
They supply nourishment to the central portion, which is to develop the
plumula and rostellum, and thus surround them. A sort of passage of
communication exists between them. There is, also, a neck between the
plumula and rostellum.
What is that scar upon the seed?
The point at which it was attached in its vessel.
Well, now I think I really do understand all the mysteries of tree
growing. Like as a young animal suckles its parent until strong enough
to manage other food, so does a young plant depend upon the cotyledon
for provision, until its rootlets are able to search the soil, and
leaflets absorb from the air.
I trust, my boy, that while you admire the order and adaptation, you
will acknowledge Him whose wisdom planned the whole, whose power
performed it, and whose goodness makes it serve the happiness of His
creatures.
* * * * *
A few days after the last conversation, Willie went with his father
into the Bush among the mountains. The way was long, and the track
was rough, but various things occurred to make the journey pleasant.
The Laughing Jackass gave the boy a merry greeting, a snake peeped at
him slyly among the long grass, and then brushed off quickly to its
hole. A Porcupine raised up its quills as he passed, and then trotted
off to the scrub. But the trees,--the trees! How tall they were! How
thick they were! With the help of their handkerchiefs, Willie and his
father measured the girth of some, and found them thirty, forty, and
even fifty feet round. Most of the Stringybark and Gum trees ran up
straight as a dart, fit to thrust into some monster ship for a mast.
Then the sweet-scented shrubs on every side, the green Myrtle, the
pyramidal and beautiful Sassafras, and many others, seized upon the
boy’s imagination, until he came to a place that made him stare, and
then caper about like a Black fellow at a corrobory. What could it be?
A break in the tangled brush underwood had given him a peep down into
a valley that seemed prettier than anything he had read of in a fairy
tale. There was no rough rock, but a floor of soft moss. The most
musical of rippling creeks trickled along the vale. No other sound was
heard, for the very birds seemed afraid to disturb with their joyous
notes the silence that dwelt there. There were no Gums, no Wattles,
rising from this moss bed. Instead of these, Willie saw a lot of very
odd looking trees. They were not very tall, for they rarely rose above
12 or 15 feet. The bark was unlike anything seen elsewhere. There
were no branches, but at the top of the straight stem were several
branch-like leaves, 8, 10, and 12 feet long, with such a graceful bend
towards the valley. At the top of the stem, rising up from the place
where the leaves sprang out, was a curious curling piece, with little
shoots. The valley was full of these wonderful vegetable festooned
pillars.
Oh! Father! father! cried the boy, what are those beautiful trees down
there? I never saw any like them before.
They are Fern trees, my lad. Walk over and look closely at them.
Willie trod upon the soft carpet, and thought it damp, as well as soft.
The air, too, was so close, and felt so cold and raw, that he lost half
his pleasure already. He could not help saying so to his father.
Ah, my boy, said he, you are not the first to find nice things having
something disagreeable about them when approaching nearer to them.
Remember, that while roses have thorns, pleasures will have their
drawbacks.
Yes, I know I am often very tired after a pretty ramble, and rather
queer after a pasty.
True enough; there is only one place where happiness brings neither
fatigue nor surfeit. But let us see what is the difference between one
of these Fern trees and one of your old companions, a Gum tree.
I can tell. One is like a tree with branches and so forth; but the
other is not. Then the bark is quite different. I can see that the
leaves of the Fern tree are like those of the common Fern, which is so
troublesome in our sandy land, only they are a great deal larger.
But there is a stranger difference still. Just take my axe and cut one
of them down.
I can soon do that. It is not nearly so thick as that Wattle I fetched
down the other day with not a dozen cuts.
Willie doffs his jacket, catches at the axe, and is at once dropping
it in double quick time upon the Fern stem. A dozen blows were given,
and another, and another, but the tree did not fall. Taking breath, and
wiping his forehead, Willie murmured out:--
Well this is tough! it beats my Wattle, hollow. I declare if the
axe don’t ring against it as if it were iron or glass. It is quite
different from one of our trees, for that is rather soft at the
outside, though it may get harder as we get towards the middle.
As I think you are more likely to blunt my axe, than cut down the tree,
you may put on your jacket, and we will inspect that fallen fern I
see yonder. Perhaps after you have looked at the inside, you will find
another wonder.
It was not long before our young Botanist uttered an exclamation of
joyful surprise.
I have found it out, said he. Only fancy, father, I was hammering away
at a mere shell, though it was a hard one. The tree is quite soft
inside, though like flint outside. It is the very opposite to every
tree I ever saw before in all my life.
No doubt it is; and it was to see it with your own eyes that I brought
you here to the Fern tree valley.
Thank you, dear father, you always like to give me a treat, and this
is a rare one, too. But I am sure that such a tree as this could never
grow like a vegetable Gum tree, that you were telling me all about.
Can you name any plants, Willie, of which the fern tree puts you in
mind?
I know of none, unless it be the Bamboo, for that is hard outside and
hollow within, and it seems, like this, to grow up straight about the
same thickness throughout.
There is another tree of this character which we have in Australia,
some kinds of which grow in other countries, producing dates, of which
boys are so fond.
Any one can guess that:--it is the Palm. But whence have we Palms,
father?
There are some in Gipps’ Land, at the foot of the Australian Alps;
other finer ones are at Illawarra, south of Sydney; but more northerly,
in the hotter parts, Palms are very common.
Is that one from which we get our Cabbage Tree Hats?
It is so. The head of the Cabbage Palm is so good tasting and
nourishing, that many trees were felled on purpose to get at this sort
of cabbage, especially in the early days of the New South Wales Colony.
Then Palms, and Bamboo, and Fern trees grow the same way, as their
stems look the same, and as they have neither branches nor solid
timber. But how do they grow, father? There is no new wood formed
outside the last ring, as in the Gum tree.
It so happens, my boy, that new layers are formed for a while, inside
instead of outside. Our new class of trees are, therefore, called
_Endogenous_, from their growing internally, in opposition to the
ordinary forest trees, which are _Exogenous_, from growing externally.
I suppose the new shoots arise from where we see the joints in the
cane; but where is the fruit of our new Endogenous friend?
Have you never seen the pictures of bunches of dates and other fruits
all among the leafy branches at the top?
Eh! that I have, with the figures of Blacks climbing up the long poles
to get at the fruit.
Now I have two more hard words for you to learn, to distinguish our
two sorts of trees. We know them not merely by the difference of wood,
but of seed. First tell me how many cotyledons or lobes are in a seed?
There are two in all the seeds that ever I saw.
What! was that cocoa nut the same which you bought the other day?
No, that was all in one piece.
True, Willie; and you may recollect something about a date stone.
I do, indeed; that was single also. I see I must not be so sure another
time about what I know. Now I understand. Our new friends of the hard
shell stems, which bear fruit at all, have seeds of one piece instead
of two.
Quite so. Now a plant of one cotyledon in its seed, is said to be
_Monocotyledonous_, while that having two lobes is _Dicotyledonous_;
_mono_ meaning one, and _di_, two.
Then my Gum tree, and Rose tree, and Sweet Pea, are all Dicotyledonous;
but the nice Date Palm, the pretty Orchis, and the sweet Cocoa-nut, are
Monocotyledonous. But are there any plants which are neither one nor
the other?
There are some whose seeds are not to be distinguished, and are known
as _Acotyledonous_, or _without cotyledons_. Can you not name one?
I don’t know, unless you mean such as the Ferns, the Mosses, and the
Lichens on the rocks or decaying timber.
They are the very ones. We have now had examples of the three great
varieties of vegetation; _Monocotyledonous_, having one lobe to the
seed; _Dicotyledonous_, having two lobes; and _Acotyledonous_, without
any.
Will you now, dear father, explain the way in which the
Monocotyledonous plants differ from the Dicotyledonous, especially in
their system of growth?