50 DIRECT INJURIES CAUSED BY INSECTS. 
But besides these Acarine diseases, there seems to be one (unless with 
Linné we regard the plague as of this class!) more fearful and fatal than 
them all. You will, perhaps, conjecture I am speaking of that described 
by Aristotle and Sir E, Wilmot as the Phthiriasis, and your conjecture 
will be right. But some think, and those men of merited celebrity, that 
miles have nothing to do in these and similar cases, for that maggots 
were the parasites mistaken for lice. This, from the passage above 
quoted, appears to have been Dr. Willan’s opinion, to which, in the letter 
so often referred to, Dr. Bateman subscribes, adding as a reason for ex- 
cluding mites from being concerned, that “they are too minute, and 
never have been seen in such numbers as to be mistaken for lice.’ But 
both vary in size, some of the former being larger than some of the latter. 
And allowing them to be ever so minute, yet when they issue in swarms, 
as mites from a cheese, they would be very visible, were it only from 
their motion. Besides, as they are furnished with legs, their motions 
resemble those of lice infinitely more than do the contortions of maggots. 
So that a mite would be deemed a louse much sooner by an unentomo~- 
logical observer than would a maggot. Whether mites have ever been 
seen in such numbers as to be mistaken for lice, is the point in question, 
and therefore, by itself, cannot be admitted for a valid argument. Though 
Acarus Scabiei does not appear to swarm in ordinary cases, yet this is 
certainly no reason why other species may not do so. Where it has 
once made a settlement, how incredibly, and in how short a space of time, 
does the Siro or cheese-mite multiply! Acarus destructor and many other 
species are equally rapid in their increase.—Millions of lice are said by 
Lafontaine, whom Hermann calls a very exact describer, to show themselves 
in Plica polonica, on the third day of the disease*; but whether the last- 
mentioned author be correct in thinking it more probable that they are 
mites®, I have not the means of judging. 
I shall now produce two instances where mites were evidently con- 
cerned. Dr. Mead, from the German Uphemerides, relates the miserable 
case of a French nobleman, from whose eyes, nostrils, mouth, and urinary 
passage, animalcules of a red colour, and excessively minute, broke forth 
day and night, attended by the most horrible and excruciating pains, and 
at length occasioned his death. The account further says, that they 
were produced from his corrupted blood. This was probably a fancy 
originating in their red colour; but the whole history, whether we con- 
sider the size and colour of the animals, or the places from which they 
issue, is inapplicable to darve or maggots, and agrees very well with 
mites, some of which, particularly Leptus autumnalis, are of a bright red 
colour. The other case, and a very similar one, is that recorded by 
Mouffet of Lady Penruddock, concerning whom he expressly tells us, 
that Acari swarmed in every part of her body—her head, eyes, nose, lips, 
gums, the soles of her feet, &c., tormenting her day and night, till, in spite 
of every remedy, all the flesh of her body being consumed, she was at 
length relieved by death from this terrible state of suffering. Mouffet 
attributes her disease to the Acarus Scabici, but from the symptoms and 
history of this parasite in his report in the Nouv. Ann, du Mus. iv, 218. See also 
Raspail’s Mémoire Gone any sur ? Hist, Nat. de VInsecte de la Gale. 
1 Amen. Ac. ubi supr. 101. 
2 Traités de Chirurgie, &c. Leipsig, 1792. 5 Mim, Apterolog. 78. 
