Gr. H. F. Nuttall 
105 
Leeuwenhoek’s Raising Experiment. This astute observer determined 
to carry out the experiment on himself “at the expense only of enduring 
on one leg, what most poor people are obliged to suffer on their whole 
bodies during all their lives.” Instead of the white stocking usually 
worn, he used “a fine black stocking, choosing that colour, because I 
considered that the eggs and the young lice thence proceeding, would be 
more easily distinguished upon it. Into the stocking I put two large 
female lice, and cutting another black stocking into long strips, I bound 
it over the first above the knee, to prevent their escaping. After 
wearing this stocking six days, I took it off, and found one of the lice 
in the same place where I had put it, and that it had laid fifty eggs, 
and in another part of the stocking the other had laid about forty eggs, 
but the parent I could not find. I opened the other which had laid 
fifty eggs, and found in its body at least fifty more, and who knows how 
many eggs it had laid before I put it into the stocking, and how many 
more eggs it might then have in its body which my sight could not 
reach ? ” 
After a further period of ten days, he found some 25 lice of different 
sizes in the stocking; he judged that they were freshly emerged and 1-2 
days old, and one egg was about to hatch. “But I was so disgusted at 
the sight of so many lice, that I threw the stocking containing them into 
the street; after which I rubbed my leg and foot very hard, in order 
to kill any louse that might be on it, and, repeating the rubbing four 
hours afterwards, I put on a clean white understocking.” 
Wilder (1911, p. 87) followed Leeuwenhoek’s method, but placed the 
stocking and the contained lice upon a patient’s leg. He allowed many 
females to oviposit and let the eggs hatch in situ,, but did not continue 
the experiment. No further experiments of the kind have been carried 
out to my knowledge. 
The Felt Cell Method. 
The method used by me for raising corporis through its life cycle 
upon the body was as follows: A thick (0-5 cm.) oblong piece of dark 
blue felt was made into a cell, an oval aperture, measuring 5x4 cm., 
being cut in the centre. The felt cell was laid upon the forearm, and 
folded strips of felt and cloth were laid into the oval space, so as to 
afford interstices corresponding to the seams in clothing, into which the 
introduced lice could retreat at will. A small piece of black sateen was 
next laid upon the cell, and the whole covered by a thin black stocking, 
the foot of which had been cut off. Beneath both ends of the stocking, 
