her spider-like fly is the Chionea valga
(Fig. 96; and 97, larva of the European species), which is a degraded
Tipula, The latter genus standing near the head of the Diptera. The
Chionea, according to Harris, lives in its early, stages in the ground
like many other gnats, and is found early in the spring, sometimes
crawling over the snow. We have also figured and mentioned previously
(page 41) the Bee louse, Braula, another wingless spider-like fly.

[Illustration: 96. Spider fly.]

[Illustration: 97. Larva of Spider fly.]

The Flea is also a wingless fly, and is probably, as has been suggested
by an eminent entomologist, as Baron Osten Sacken informs us, a degraded
genus of the family to which Mycetobia belongs. Its transformations are
very unlike those of the fly ticks, and agree closely with the early
stages of Mycetophila, one of the Tipulid family. In its adult condition
the flea combines the characters of the Diptera, with certain features
of the grasshoppers and cockroaches, and the bugs. The body of the flea
(Fig. 98, greatly magnified; _a_, antennae; _b_, maxillae, and their
palpi, _c_; _d_, mandibles; the latter, with the labium, which is not
shown in the figure, forming the acute beak) is much compressed, and
there are minute wing-pads, instead of wings, present in some species.

[Illustration: 98. Flea, magnified.]

[Illustration: 99. Larva of Flea.]

Dr. G. A. Perkins, of Salem, has succeeded in rearing in considerable
numbers from the eggs, the larvae of this flea. The larvae (Fig. 99, much
enlarged; _a_, antenna; _b_, the terminal segments of the abdomen), when
hatched, are half a line in length. The body is long, cylindrical, and
pure white, with thirteen segments exclusive of the head, and provided
with rather long hairs. It is very active in its movements, and lives on
blood clots, remaining on unswept floors of out-houses, or in the straw
or bed of the animals they infest. In six days after the eggs are laid
the larvae appear, and in a few days after leaving the egg they mature,
spin a rude cocoon, and change to pupae, and the perfect insects appear
in about ten days. A good authority states that the human flea does not
exist in America. We never saw a specimen in this country.

A practical point is how to rid dogs of fleas. As a preventive measure,
we would suggest the frequent sweeping and cleansing of the floors of
their kennels, and renewing the straw or chips composing their
beds,--chips b