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ANOPLURA 207
The human louse, Pediculus humanus Linnreus( = capitis DeGeer, corporis
DeGeer, vestimenti Nitzsch), is an average-size member of the order, measuring
from 2.00-3.25 mm. in length for the males and from 2.5-4.2 mm. in length for
the females. It is a pale-colored species with dark markings along the sides.
t.
FIG. 75. The human louse. Pediculus humanus Linn. Adult female, and eggs
attached to a hair. (From 11 History oj Entomology,)
The eggs or nits are glued to hairs or to clothing and hatch in from 6 to 9 days.
The young reach maturity in about 18 days. The entire life history is spent
upon the body and in the clothing of the host. The lice not only cause severe
itching and eczema-like eruptions of the skin. known as pediculosis, but they
act as carriers and transmitters of such serious diseases as typhus fever, trench
fever, and European relapsing fever. Perhaps only the honeybee and the silk.
worm have played more important parts in entOmological literature than this
louse, which has long been discussed under two names, the body louse and the