April 22, 19 
 
Mr. A. B. Andrews 
 
I have't found anyone who has enough reeords to 
wther chi6agrs are cyclie or not. However, Dr. V. 1. "he' 
has reoords on populations of woodland spiders for many yewz 
finds that these forms are cyclic. It is suspected that ch 
(whieh are grassland mites) are also cyclie. 
Thank you again for your letter. If we find this 
of parasitism on pheasants in Illinois this oumnur or later 
let you know. I recently sent some of our publications to 
V,0,40 
 
S incerely yours, 
 
&Ialph '. Yeatter 
Game Specialist 
cc: Prof. Aldo Leopold 
)Dr. Irven 3uss 
P 
Yo