Action of heat: In the course of my biological study, I have made a number of observations on the influence of heat. The action of this element is so important that I have carried out a series of experiments in order to understand it better. I have submitted the insect in all of its stages of life to the action of temperatures varying from in the neighborhood of zero through freezing to the death point of 46° C., in an air conditioning chamber. According to the stage of the insect, it has reacted in a special way.