4 INTRODUCTION 



habits and development of the fly. It was natural that he 

 should make some errors, such as mistaking the brown testes 

 for the kidneys, in attempting to describe the anatomy at so 

 early a date of our knowledge of morphology and methods of 

 study. Notwithstanding these limitations, Gleichen's was still 

 the most comprehensive and detailed account of the house-fly 

 when I commenced to study the insect. 



A short popular account of the house-fly was published, con- 

 jointly with that of the earth-worm, by Samuelson and Hicks 

 in 1860, in a book entitled Humble Creatures. Though inte- 

 resting, the account is very superficial and contains much that 

 is inaccurate. 



In 1874 Packard wrote a fairly complete account of the de- 

 velopmental history of the house-fly as observed in Massachusetts, 

 U.S.A., and in 1880 Taschenberg gave a good popular account 

 of the insect and its breeding habits in his Praktische Tnsekten- 

 kunde. 



Howard gave a short account of the life-history of the house- 

 fly in a bulletin on household insects, published in 1896 by the 

 United States Department of Agriculture, and he gave a further 

 account in 1900, in a valuable paper on the insect fauna of 

 human excrement. Newstead, in 1907, gave a preliminary 

 report of his study of the development and breeding-places of 

 the house-fly in the city of Liverpool, and a second report was 

 published in 1909. 



Space forbids the enumeration of the countless papers and 

 accounts of the house-fly which have been wTitten during the 

 past two or three years. Some of these contain original infor- 

 mation, the majority of them do not. Of recent publications, 

 Howard's popular book on the house-fly (1911) should be men- 

 tioned, not only as being a complete account of the insect and 

 its disease-carrying powers, but because it contains many original 

 observations^ Special reference should be made to the valuable 

 series of papers published in connection with an inquiry carried out 

 by the Local Government Board on flies as carriers of infection. 



1 Since the above lines were written Graham-Smith has given an excellent 

 account of the disease-carrying powers of the non-blood-sucking flies in his Fliea 

 and I)isca!<e (1913); see Bibliography. 



