The Guts are of a pure green Colour after feeding, and appear branched over with little
capillary white Veins. It has also Liver, Spleen, Stomach, Mouth, and Teeth (which have
been just now described) and semi-spherical Eyes at the Tips of the Horns, which if cut
off and examined look like large blue Beads.
PLATE XXIII. FIG. 2.
The Egg of a Silk-Worm
THE minute Egg of this little Animal, when magnified by Glasses, exhibits an Ap-
pearance well worthy our Admiration ; for innumerable Cavities or Hollows, ex-
tremely small, with Risings interposed, somewhat resembling those on a Poppy-Seed, over-
spread its whole Surface : But the Cavities and Ridges here are less an hundred times than
those on the Seeds of Poppy, and not distinguishable without a good Instrument and a
When the Young is hatched, and the Shell broke, it seems no thicker, in proportion to
its Bigness, than the Egg-shell of a Goose or Hen. It looks then of a pure white, and
so transparent, that none of the little Pits on its Surface can be discerned, without great
Difficulty : But a most delicate thin Film may be discovered lining its Inside, in the man-
ner of large Eggs ; the Shell itself is very brittle.
The Figure of these Eggs is not exactly round, but somewhat flatted both on the upper
and under Side ; and the included Insect may be discovered lying coiled near the Edges of
it. But several other Sorts of Moths lay Eggs exactly globular, with Surfaces perfectly
smooth and polished ; and there is no less Variety in the Eggs of Insects than in those of
These Eggs hatch sooner or later in the Spring, according to the Warmth of the Wea-
ther ; and may be forwarded very much by keeping them in a certain Degree of Heat.
The young Brood appears at first to be a Number of black hairy little Catterpillars, bearing
not the least Resemblance to the Forms they afterwards assume. As therefore the Manner
of their Changing is wonderful, and many may be desirous to see it with their own Eyes,
some short Directions how to feed and manage them, though not altogether requisite in
this Place, will not, 'tis hoped, be judged impertinent.
Directions how to breed Silk-worms in England
IN China, India, and some other hot Countries, the Silk-worms live abroad in the open
Air, upon Mulberry-Trees propagated in great Abundance for their Reception. On
these they feed, expatiating in full Liberty, till they inclose themselves in Bills of Silk,
curiously fastned to the Branches, and appearing like golden Apples amidst the beautiful
Green that embellishes and contrasts them. Here too they affix their Eggs on Parts of the
Tree proper for their Preservation, with a Sort of Glew bestowed on them by Providence
for that purpose ; where they remain secure all the Autumn and Winter-Season, nor begin
to hatch till the young expanding Leaves afford them abundant Sustenance.
But in our cold Climate, these Creatures must be treated in a quite different manner,
and preserved in Houses with a great deal more Care and Trouble. As soon as they are
hatched, which is commonly some time in May, and before the Mulberry Leaves come
out, the Papers on which the Eggs are laid with us, are to be placed in a Sheet of stiff
Writing-Paper, (turned up on every side in the Fashion of a Dripping-Pan) laying lightly
upon them the young tender Leaves of Lettice. On these they will crawl and feed ; and
a fresh Supply must be given them as often as the Leaves grow withered ; taking care to
help some of them off the withered Leaves by the Assistance of a Pin ; without which
many will be thrown away or destroyed. For a Thread which issues from their Mouths,
and by sticking to whatever it touches, preserves them from the Danger of falling, sometimes
binds them down so fast to the old Leaves, that they become unable to quit them without
a little Assistance.
In a few Days, the little Catterpillar that was black at first, approaches nearer to an
ashen Grey : Its Coat appears ragged, the Animal casts it off, and is seen in a new Habit.
It increases in Bigness, and grows whiter, with a little Tendency to green. Some Days
after this, it forbears eating, and sleeps almost two Days, at the End whereof it seems
agitated and convulsed, and grows almost red with the Violence of its Struggles : The