This two volume work covers the immature stages of our macrolepidoptera. For each species there is generally a half-tone photograph of the ova, a colour painting of the larva and a half-tone reproduction of a painting of the pupa. Unfortunately the quality of the plates is rather poor, being limited by the print technology of the day.

The species accounts give short shrift to the adult, as this is covered elsewhere, but describe the eggs, caterpillar and chrysalis. The foodplants are listed.

A companion work to South’s "The Moths of the British Isles", for many years this was the bible for identifying larval statges, but has now been superseded by Porter. It remains the best means of identifying eggs or pupae.