Micrographia, by Robert Hooke

Observ. lvi. Of a small Creature hatch'd on a Vine.

There is, almost all the Spring and Summer time, a certain small, round, white Cobweb, as 'twere, about the bigness of a Pea, which sticks very close and fast to the stocks of Vines nayl'd against a warm wall: being attentively viewed, they seem cover'd, upon the upper side of them, with a small husk, not unlike the scale, or shell of a Wood-louse, or Hog-louse, a small Insect usually found about rotten wood, which upon touching presently rouls it self into the form of a peppercorn: Separating several of these from the stock, I found them, with my Microscope, to consist of a shell, which now seemed more likely to be the husk of one of these Insects: And the fur seem'd a kind of cobweb, consisting of abundance of small filaments, or sleaves of cobwebs. In the midst of this, if they were not hatch'd, and run away before, the time of which hatching was usually about the latter end of June, or beginning of July, I have often found abundance of small brown Schem. 36.
Fig. 2.
Eggs, such as A and B in the second Figure of the 36. Scheme, much about the bigness of Mites Eggs; and at other times, multitudes of small Insects, shaped exactly like that in the third Figure marked with X. Its head large, almost half the bigness of its body, which is usual in the fœtus of most Creatures. It had two small black eyes aa, and two small long joynted and brisled horns bb. The hinder part of its body seem'd to consist of nine scales, and the last ended in a forked tayl, much like that of a Cutio, or Wood louse, out of which grew two long hairs; they ran to and fro very swiftly, and were much of the bigness of a common Mite, but some of them less: The longest of them seem'd not the hundredth part of an inch, and the Eggs usually not above half as much. They seemed to have six legs, which were not visible in this I have here delineated, by reason they were drawn under its body.

If these Minute creatures were Wood-lice (as indeed from their own shape and from the frame, the skin, or shell, that grows on them, one may with great probability ghess) it affords us an Instance, whereof perhaps there are not many like in Nature, and that is, of the prodigious increase of these Creatures, after they are hatch'd and run about; for a common Wood-louse, of about half an inch long, is no less then a hundred and twenty five thousand times bigger then one of these, which though indeed it seems very strange, yet I have observed the young ones of some Spiders have almost kept the same proportion to their Dam.

This, methinks, if it be so, does in the next place hint a Quæry, which may perhaps deserve a little further examination: And that is, Whether there be not many of those minute Creatures, such as Mites, and the like, which, though they are commonly thought of otherwise, are only the pully, or young ones, of much bigger Insects, and not the generating, or parent Insect, that has layd those Eggs; for having many times observ'd those Eggs, which usually are found in great abundance where Mites are found, it seems something strange, that so small an Animal should have an Egg so big in proportion to its body. Though on the other side, I must confess, that having kept divers of those Mites inclosed in a box for a good while, I did not find them very much augmented beyond their usual bigness.

What the husk and cobweb of this little white substance should be, I cannot imagine, unless it be, that the old one, when impregnated with Eggs, should there stay, and fix it self on the Vine, and dye, and all the body by degrees should rot, save only the husk, and the Eggs in the body: And the heat, or fire, as it were, of the approaching Sun-beams should vivifie those Relicts of the corrupted Parent, and out of the ashes, as 'twere, (as it is fabled of the Phœnix) should raise a new offspring for the perpetuation of the Species. Nor will the cobweb, as it were, in which these Eggs are inclos'd, make much against this Conjecture; for we may, by those cobwebs that are carried up and down the Air after a Fog (which with my Microscope I have discovered to be made up of an infinite company of small filaments or threads) learn, that such a texture of body may be otherwise made then by the spinning of a Worm.

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Last updated Monday, March 17, 2014 at 16:42