Diptera

Abstract

On comparing the Kerguelen Island Diptera with their nearest foreign allies, some are found to have retained the habits of the families to which they belong, and not to have departed in any way from their normal condition. These are they which frequent the denser portions of the herbage, and are efficiently sheltered by it even when the weather is at its worst, e. g ., the Sciara and the Limnophyes . A larger number, also remaining true to the habits of their kindred, are less protected from the cold than the forms before mentioned, being denizens of rocks and crevices; these have small rudimentary wings (one is apterous) and a fair amount of hair and bristles (the apterous species being the worst off in these respects). Another is likewise constant to the habits of its nearest relations; and in conse­quence it is more exposed to the rigours and vicissitudes of the climate than any of the other species, frequenting as it does the leaves of the Kerguelen Island cabbage ( Pringlea ) ; it is almost apterous, and its hair and bristles are of the most rudimentary description. The Diptera of the Falkland Islands have their wings fully developed.