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THE MEDITERRANEAN FLOUR MOTH (Ephestia kuehniella 

 Z.llei) IN EUROPE AND AMERICA. 



By Willis Ghant Johnson, A. M. 



INTRODUCTORY. 



Insect injuries in flouring-mills have been known from time 

 immemorial, but not until recent years have they attracted public 

 attention. The mild and equable temperature which is maintained 

 in the modern mill is highly favorable to the development and 

 multiplication of those pests commonly called "mill insects." The 

 most formidable enemy in this group is the Mediterranean flour 

 moth, Ephestia kuehniella Zell., an insect unknown to American 

 millers less than seven years ago. The discovery of this terrible 

 scourge in Canada in 1889, in California in 1892, and in New 

 York and Pennsylvania in 1895, has awakened a keen interest in 

 the subject among milleis and scientifiic workers. 



Its discovery in California in March, 1892, led me to a carefnl 

 examination of all available literature on the subject. I found 

 this material so scattered that I have deemed it advisable to bring 

 it together and to embody it substantially in this paper which 

 covers my own observations and experimental work on this insect. 

 Most of these observations were made in California, where also a 

 large part of my experimental work on. life history and methods 

 of destruction was carried on. Much additional information has, 

 however, been gained by experimentation and correspondence 

 since my connection with the Illinois State Laboratory of Natural 

 History. 



I wish to express here my thanks to Mr. L. O. Howard, U. S. 

 Entomologist, Washington, D. C, through whose kindness I ob- 

 tained Figures 1, 2, 3, and 5 from the U. S. Department of Ag- 

 riculture. I also beg to acknowledge, with thanks, the kindness 

 of Mr. James Fletcher, of the Department of Agriculture of 

 Ottawa, Canada, in furnishing me with his exhaustive reports con- 

 taining articles on this subject, and the courtesy of Dr. P. H. Bryce, 

 Secretary of the Provincial Board of Health of Ontario, Canada, 

 in sending me his excellent Bulletin and circular letter on the 

 flour moth. I am also indebted to Miss E. A. Ormerod, late Consult- 

 ing Entomologist of the Royal Agricultural Society of England, 

 for her complete accounts of the moth in England; and to Mr. J. 

 Danysz, Director of the Laboratory of Parasitology and of the Cham- 



