s black, with metallic green reflections, and
the legs are dark and paler at the knee-joints, the middle and hind pair
of tarsi being dark honey yellow. The Wine fly is also a Piophila, and
lives the life of a perpetual toper in old wine casks, and partially
emptied beer, cider and wine bottles, where, with its pupa-case (Fig.
91), it may be found floating dead in its favorite beverage.

[Illustration: 92. Bird Tick.]

We now come to the more degraded forms of flies which live parasitically
on various animals. We figure, from a specimen in the Museum of the
Peabody Academy of Science, the Bird tick (Ornithomyia, Fig. 92), which
lives upon the Great Horned Owl. Its body is much flattened, adapted for
its life under the feathers, where it gorges itself with the blood of
its host.

[Illustration: 93. The Horse Tick.]

Here belongs also the Horse tick (Hippobosca equina, Fig. 93). It is
about the size of the house fly, being black, with yellow spots on the
thorax. Verrill[4] says that "it attacks by preference those parts where
the hair is thinnest and the skin softest, especially under the belly
and between the hind legs. Its bite causes severe pain, and will
irritate the gentlest horses, often rendering them almost unmanageable,
and causing them to kick dangerously. When found, they cling so firmly
as to be removed with some difficulty, and they are so tough as not to
be readily crushed. If one escapes when captured, it will instantly
return to the horse, or, perchance, to the head of its captor, where it
is an undesirable guest. Another species sometimes infests the ox."

[Illustration: 94. Sheep Tick.]

[Illustration: 95. Bat Tick.]

In the wingless Sheep tick (Melophagus ovinus, Fig. 94, with the
pupa-case on the left), the body is wingless and very hairy, and the
proboscis is very long. The young are developed within the body of the
parent, until they attain the pupa state, when she deposits the pupa
case, which is nearly half as large as her abdomen. Other genera are
parasitic on bats; among them are the singular spider-like Bat ticks
(Nycteribia, Fig. 95), which have small bodies and enormous legs, and
are either blind, or provided with four simple eyes. They are of small
size, being only a line or two in length. Such degraded forms of Diptera
have a remarkable resemblance to the spiders, mites, ticks, etc. The
reader should compare the Nycteribia with the young six-footed moose
tick figured farther on. Anot