CERTAIN PARASITIC INSECTS. 85 
among moths the study of the wingless canker-worm moth 
and Orgyia; among Diptera the flea, bee-louse (Braula), 
sheep tick, bat ticks, and other wingless flies ; among Cole- 
optera, the Meloé, and singular Stylops and Xenos; among 
Neuroptera the snow insect, Doreus, the Podura and Lep- 
isma, and especially the hemipterous lice, will throw a flood 
of light on these prime subjects in philosophical entomology. 
Without farther apology, then, and very dependent on the 
labor of others for our information we will say a few words 
on some interesting points in the natural history of lice. In 
the first place, how does the louse bite? It is the general 
opinion among physicians, supported by able entomologists, 
that the louse has jaws, and bites. But while the bird lice 
(Mallophaga) do have biting jaws, whence the Germans 
call them skin-eaters (pelzfresser), the mouth parts of the 
genus Pediculus, or true louse, resemble in Fig. 13. 
their structure those of the bed-bug (Fig. 13, 
from the author's "Guide to the Study of In- 
sects”) and other Hemiptera. In its form the 
louse closely resembles the bed-bug, and the 
two groups of lice, the Pediculi and Mallo- 
phaga, should be considered as families of Bed-bug. 
Hemiptera, though degraded and at the base of the hemip- 
terous series. The resemblance is carried out in the form 
of the egg, the mode of growth of the embryo, and the meta- 
morphosis of the insect after leaving its egg. 
Schiódte, a Danish entomologist, has, it seems to us, 
forever settled the question as to whether the louse bites 
the flesh or sucks blood, and decides a point interesting 
to physicians, 7.e. that the loathsome disease called phthiri- 
asis, from which not only many living in poverty and squalor 
are said to have died, but also men of renown, among 
whom Denny in his work on the Anoplura, or lice, of Great 
Britain, mentions the name of "Pheretima, as recorded by 
Herodotus, Antiochus Epiphanes, the Dictator Sylla, the 
two Herods, the Emperor Maximian, and Phillip the Sec- 
a—À 
