STUDIES IN THE MIGRATION OF LEPIDOPTERA

Abstract

a survey of the evidence available on the subject of the migration of buttedies, and discussed many of the problems arising out of an analysis of this evidence.In the intervening ten years considerable progress has been made and in particular the collection and study of records have been greatly facilitated by three events.Firstly, in 1931 a group of amateurs was organised by Captain T. Dannreuther to observe the immigration of insects on the south coast of Britain.Under his enthusiastic leadership the organisation has spread to cover the greater part of the British Isles, with its nucleus in the " Insect Immigration Committee " of the South-Eastern Union of Scientific Societies.Through its action numerous records have been sent in not only from the land but also, with the co-operation of Trinity House, from the lightships and lighthouses off our coast.Secondly, in 1937 the National Geographic Society of America published in their magazine a semi-popular article on Butterfly Migration (Williams 1937a).This magazine has a monthly circulation of over a million copies and, as a result of the publicity obtained, between two and three hundred correspondents sent in their observations.Some of these have continued to co-operate and have produced information of first-class importance.Finally, in 1938