The insects belonging to this section much resemble spiders in
appearance. They are all parasitic, and are remarkable for the perfect
insect producing its young singly, and that not in the egg state, as in
most insects, but either in the _pupa_ state, or as a mature _larva_
ready to become a _pupa_ immediately. This tribe contains only three
families.
_Family 36, Hippoboscidæ._--The most familiar insects comprised in this
family are known as "Forest Flies." The common Forest Fly (_Hippobosca
equina_) is a brown species about one-third of an inch in length, and
exceedingly annoying to horses, particularly in the New Forest. The
Sheep Tick (_Melophagus ovinus_) is another well-known example.
[Illustration: Fig. 154.--Oscinis Cornuta (Mag.)]
_Family 37, Nycteribidæ._--These insects are all parasitic on bats, and
are commonly known as "Bat Lice." They are wingless, but have a pair of
halteres placed upon the dorsal surface.
[Illustration: Fig. 155.--Phora Camariana (Mag.)]
_Family 38, Braulidæ._--This family includes only a single species,
which is parasitic upon the honey bee. Its name is _Braula cæca_, and
it is an exceedingly minute creature.