Hooke comments on the louse’s appearance and watches one feed on his blood
This is a Creature so officious, that ’twill be known to every one at one time or other, so busie, and so impudent, that it will be intruding it self in every ones company […]
The louse’s eyes
[…] it is a Creature of a very odd shape; it has a head […] which seems almost Conical, but is a little flatted on the upper and under sides, at the biggest part of which, on either side behind the head […] are placed its two black shining goggle eyes, looking backwards, and fenced round with several small cilia, or hairs that incompass it, so that it seems this Creature has no very good foresight: It does not seem to have any eye-lids, and therefore perhaps its eyes were so placed, that it might the better cleanse them with its fore-legs; and perhaps this may be the reason, why they so much avoid and run from the light behind them, for being made to live in the shady and dark recesses of the hair, and thence probably their eye having a great aperture, the open and clear light, especially that of the Sun, must needs very much offend them; to secure these eyes from receiving any injury from the hairs through which it passes, it has two horns that grow before it, in the place where one would have thought the eyes should be […]
Hooke watches a louse suck his blood
[…] having kept several of them in a box for two or three dayes, so that for all that time they had nothing to feed on, I found, upon letting one creep on my hand, that it immediately fell to sucking, and did neither seem to thrust its nose very deep into the skin, nor to open any kind of mouth, but I could plainly perceive a small current of blood, which came directly from its snout, and past into its belly; and […] there seem’d a contrivance, somewhat resembling a Pump, pair of Bellows, or Heart, for by a very swift systole and diastole the blood seem’d drawn from the nose, and forced into the body. It did not seem at all, though I viewed it a good while as it was sucking, to thrust more of its nose into the skin […], nor did it cause the least discernable pain, and yet the blood seem’d to run through its head very quick and freely, so that it seems there is no part of the skin but the blood is dispers’d into, nay, even into the cuticula; for had it thrust its whole nose in […], it would not have amounted to the supposed thickness of that tegument, the length of the nose being not more then a three hundredth part of an inch.
The louse’s legs
It has six legs, covered with a very transparent shell, and joynted exactly like a Crab’s, or Lobster’s; each leg is divided into six parts by these joynts, and those have here and there several small hairs; and at the end of each leg it has two claws, very properly adapted for its peculiar use, being thereby inabled to walk very securely both on the skin and hair; and indeed this contrivance of the feet is very curious, and could not be made more commodiously and compendiously, for performing both these requisite motions, of walking and climbing up the hair of a mans head, then it is […].