THE SURVIVAL OF THE FITTEST AMONG CERTAIN SPECIES OF PTEROSTICHUS AS DEDUCED FROM THEIR HABITS

Extract

The ultimate extinction of many species of Coleoptera in the vicinity of large cities is unquestionable, especially of the larger Carabidæ. The conditions of life with some are such as admit of no adaptation to the methods of civilization, and for them no refuge from the encroachments of agriculture will eventually remain. They are now retiring, retiring, and in time the last goal will be reached. In localities where the population is becoming dense, and all land available placed under cultivation, many fine species that once were common are now rarities and others fast becoming so. It is less than half a century since Mr. Randall described eighty four species from localities in Maine and Massachusetts, most of them common; but, according to Mr. Austin, in the same places several of these species are now extinct and many of them have become rare.