trees, and bites the skin in its efforts to relieve the irritation. On
examining the coat, nits are found adhering to the hair (Fig. 65). We
should examine the parts of the skin covered by the long hair for the
sucking lice; and the withers, abdomen and limbs for the biting lice.

[Illustration: FIG. 64.--Sucking louse (much enlarged).]

[Illustration: FIG. 65.--Nits attached to hair (much enlarged).]

_The symptoms of lousiness in cattle_ are about the same as occur in
horses. Licking and rubbing the skin are prominent symptoms in cattle, and
the coat becomes dirty and rough. The licked part is matted and curled. The
lice may be discovered by parting the hair along the back and rump.

_The biting louse of sheep_ causes the fleece to become matted and tufts of
wool are pulled out. This is brought about by the sheep rubbing and
nibbling the fleece, and the lice cutting through the wool. The loss due to
the damage to the fleece is usually greater than that resulting from
unthriftiness.

_The hog-louse_ is the largest specie known. As well as the largest, it is
the most common of all lice found on domestic animals. The favorite points
of attack are the under surface of the body, the neck and the inside of the
thighs. The irritation and itching are severe, and the hog rubs and
scratches the skin. Young hogs suffer most from this parasite, and their
thriftiness is greatly interfered with.

The long-haired breeds of _dogs_ suffer more from lice than the
short-haired breeds. The almost constant scratching and biting of the skin
result in its becoming badly irritated and scabby. The symptoms differ