It may also be used beneficially in preventing the attacks of insects, such as the onion gnat and turnip fly, by dusting the plants or dressing the ground with it.
To this life-cycle belongs the formation of sexual individuals and their conjugation on arrival in the gnat (Culex); the process is described as agreeing in the main, in both cases, with what has already been made known by MacCallum for another species of Halteridium.
Their insect origin appears to have been entirely unsuspected until within comparatively recent times, though Pliny, indeed, makes the observation that a kind of gnat is FIG.
It is the northernmost home of the opossum, grey fox, fox squirrel, cardinal bird, Carolina wren, tufted tit, gnat catcher, summer tanager and yellow-breasted chat.
A gnat pupa swims through the water by powerful strokes of its abdomen, while the caddis-fly pupa, in preparation for its final ecdysis, bites its way out of its subaqueous protective case and rises through the water, so that the fly may emerge into the air.
The motile copula or ookinete formed in the gnat gives T.
The distribution of the parasites in the gnat is closely connected with the process of digestion.
The gnat larva, for example, breathes at the tail-end, hanging head-downwards from the surface-film.
As the common gnat (Culex pipiens), are rarely found away from human habitations; others seldom or never enter houses, but are met with either in more or less open country, or in the recesses of forests and woods.
Schaudinn (50), who investigated certain avian Trypanosomes, considered the latter view to be correct, and believed that the carrier - in this instance a gnat - is indeed the definitive host, i.e.