His major butterfly works include the two volume Natural History of British Butterflies (1924) and The Complete Book of British Butterflies (1934). In 1927, a need for money forced him to sell his butterfly collection to Lord Rothschild for £1000. These are now part of the Rothschild collection in the Natural History Museum at London. He also illustrated numerous bird books, including Aves Hawaiienses: The Birds of the Sandwich Islands; and Birds of the British Isles and their Eggs with A G Butler, published around 1898.
