7 
THE MEDITERRANEAN FLOUR MOTH (Ephestia lmehniella 
Zeller) IN EUROPE AND AMERICA. 
By Willis Grant 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 careful 
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- 
