INSECTS IN RELATION 
TO 
NATIONAL DEFENSE 
Circular 23 - Reference Index 
This oiroular has been prepared for 
the purpose of making the information con- 
tained in the previous 22 circulars of the 
S«ries more readily available and useable to 
those for whose purpose the information was 
assembled. The subject matter index has been 
prepared in two parts: Part I is a general 
reference index dealing with the insects re- 
lated to national defense, and includes de- 
vices, materials, and methods useful in 
their prevention and control. Part II is a 
cross reference index to those subjects, 
such as animals, buildings, camp locations, 
diseases, foods, materials, etc. with which 
Insects are concerned in connection with nation- 
al defense. 
The references are arranged alpha- 
betically. The first number after the refer- 
ence indicates the number of the ciroular and 
numbers following the dash designate page 
numbers. References occurring in more than 
one circular are separated by a semicolon, 
and references to an illustration of the 
subject matter are preoeeded by the abrevia- 
tion (illus.): e.g. 8-17, (illus.) IS; 18-7, 
(illus.) 8 would indicate that references to 
the same subject matter occur on page 17 of 
circular 8 and on page 7 of circular 18; also 
that the subject matter is illustrated on 
page 18 of circular 8 and on page 8 of cir- 
oular 18. 
