1934 226 p., 6 photographic plates, 127 text figures, large folded map, contemporary half cloth over marbled boards. Gilt title on the spine. Marbled edges. Original printed front cover bound in. An excellent monograph with detailed descriptions, illustrations and keys, also for the larvae. Also with spurious notes on the species' distribution, seasonal occurrence, etc. The photos mainly show habitats. A well-bound, clean copy. Rare.