Additional Experiments with Pyrameis carye (Lepid.)

Abstract

<br />Every experienced lepidopterist knows that localities in which there are extreme variations in temperatures tend to produce seasonal forms of certain species of butterflies. In my breeding experiments I find that the same thermic factor is operative in the production of aberrant forms : for example — butterfly larvae which have been raised in a cool environment, and after pupation are subjected to very hot temperature, produce the greatest percentage of aberrations.