Originally published in 1925, this volume is adapted from lectures delivered by the author at the Royal Institution during the Christmas period of 1924. Its aim was principally to engage the interest of young people and provide them with the tools for increasing their own knowledge through methodical, scientific research. In this spirit, descriptions of the life histories of various insects are avoided in favour of explanations for how these life histories were worked out. Numerous illustrative figures of insects and insect habitats are also included. This is a highly readable and informative text that will be of value to anyone with an interest in entomology, natural history, and the history of education.