This volume serves as a definitive identification manual for the butterfly species inhabiting the European continent and the British Isles. Authors Lionel George Higgins and Norman Denbigh Riley synthesize decades of entomological observation to provide a systematic framework for species classification. The text utilizes detailed morphological descriptions and geographical distribution data to assist both amateur naturalists and professional researchers in the field.

This guide is regarded as a foundational reference work for European lepidopterists due to its rigorous classification standards and extensive visual documentation. The text remains a standard resource for those requiring a reliable, systematic approach to butterfly identification across diverse European ecosystems.