It is stated that several great personages have fallen victims to its attack, but these observations date from a period when it was thought that they could be spontaneously originated. It is in fact difficult to believe, as it has seriously been stated, that lice have been seen to issue from the bodies of men like a spring of water from the earth. A physician of the 16th century, named Amatus Lusitanus, speaks of a great Portuguese nobleman who was so covered with lice that two of his servants were constantly occupied in collecting them and carrying them to the sea. Andrew Murray has published a memoir on the lice of the various races of men.
The name of helminthiasis has been proposed for worm disease in general, and either tæniaceous or lumbricoidian helminthiasis, according to the species which made its appearance. These parasites were considered to be formed spontaneously, and their presence
constituted a pathological condition, two errors which have now been recognized, and by which the science of medicine has profited.
The Phthirius pubis is another species which has been found only on white races, and attaches itself especially to the hair on the pubis. Mons. Grimm has published in the bulletins of the Academy of St. Petersburg, an interesting memoir on the embryogeny of this insect; and, more recently, Mons. L. Landois, of Griefswald, has completely studied its habits.
Fig. 18.—Louse of the Head;
2, 3, sucker.
Fig. 19.—Louse of the Head, claw.