I had some old mulberry-trees in my garden. My grandfather had planted
them. In the fall I was given a dram of silkworm eggs, and was advised
to hatch them and raise silkworms. These eggs are dark gray and so small
that in that dram I counted 5,835 of them. They are smaller than the
tiniest pin-head. They are quite dead; only when you crush them do they
crack.
The eggs had been lying around on my table, and I had almost forgotten
about them.
One day, in the spring, I went into the orchard and noticed the buds
swelling on the mulberry-trees, and where the sun beat down, the leaves
were out. I thought of the silkworm eggs, and took them apart at home
and gave them more room. The majority of the eggs were no longer dark
gray, as before, but some were light gray, while others were lighter
still, with a milky shade.
The next morning, I looked at the eggs, and saw that some of the worms
had hatched out, while other eggs were quite swollen. Evidently they
felt in their shells that their food was ripening.
The worms were black and shaggy, and so small that it was hard to see
them. I looked at them through a magnifying-glass, and saw that in the
eggs they lay curled up in rings, and when they came out they
straightened themselves out. I went to the garden for some mulberry
leaves; I got about three handfuls of leaves, which I put on my table,
and began to fix a place for the worms, as I had been taught to do.
While I was fixing the paper, the worms smelled their food and started
to crawl toward it. I pushed it away, and began to entice the worms to a
leaf, and they made for it, as dogs make for a piece of meat, crawling
after the leaf over the cloth of the table and across pencils, scissors,
and papers. Then I cut off a piece of paper, stuck holes through it with
a penknife, placed the leaf on top of it, and with the leaf put it down
on the worms. The worms crawled through the holes, climbed on the leaf,
and started to eat.
When the other worms hatched out, I again put a piece of paper with a
leaf on them, and all crawled through the holes and began to eat. The
worms gathered on each leaf and nibbled at it from its edges. Then, when
they had eaten everything, they crawled on the paper and looked for more
food. Then I put on them new sheets of perforated paper with mulberry
leaves upon them, and they crawled over to the new food.
They were lying on my shelf, and when there was no leaf, they climbed
about the shelf, and came to its very edge, but they never fell down,
though they are blind. The moment a worm comes to an edge, it lets out a
web from its mouth before descending, and then it attaches itself to it
and lets itself down; it hangs awhile in the air, and watches, and if it
wants to get down farther, it does so, and if not, it pulls itself up by
its web.
For days at a time the worms did nothing but eat. I had to give them
more and more leaves. When a new leaf was brought, and they transferred
themselves to it, they made a noise as though a rain were falling on
leaves,--that was when they began to eat the new leaf.
Thus the older worms lived for five days. They had grown very large and
began to eat ten times as much as ever. On the fifth day, I knew, they
would fall asleep, and waited for that to happen. Toward evening, on the
fifth day, one of the older worms stuck to the paper and stopped eating
and stirring.
The whole next day I watched it for a long time. I knew that worms
moulted several times, because they grew up and found it close in their
old hide, and so put on a new one.
My friend and I watched it by turns. In the evening my friend called
out:
"It has begun to undress itself,--come!"
I went up to him, and saw that the worm had stuck with its old hide to
the paper, had torn a hole at the mouth, thrust forth its head, and was
writhing and working to get out, but the old shirt held it fast. I
watched it for a long time as it writhed and could not get out, and I
wanted to help it. I barely touched it with my nail, but soon saw that I
had done something foolish. Under my nail there was something liquid,
and the worm died. At first I thought that it was blood, but later I
learned that the worm has a liquid mass under its skin, so that the
shirt may come off easier. With my nail I no doubt disturbed the new
shirt, for, though the worm crawled out, it soon died.
The other worms I did not touch. All of them came out of their shirts in
the same manner; only a few died, and nearly all came out safely, though
they struggled hard for a long time.
After shedding their skins, the worms began to eat more voraciously, and
more leaves were devoured. Four days later they again fell asleep, and
again crawled out of their skins. A still larger quantity of leaves was
now consumed by them, and they were now a quarter of an inch in length.
Six days later they fell asleep once more, and once more came out in new
skins, and now were very large and fat, and we had barely time to get
leaves ready for them.
On the ninth day the oldest worms quit eating entirely and climbed up
the shelves and rods. I gathered them in and gave them fresh leaves, but
they turned their heads away from them, and continued climbing. Then I
remembered that when the worms get ready to roll up into larvæ, they
stop eating and climb upward.