July 6, 1950) 
1r. Lysle P. Itseh 
Dnartmmnt of Conservation 
Dixon, Illinois 
)ear ?,r. Pietscht 
In resTonie to your letter of June 12, Professor 
Leorold's family has given us nermission to turn over 
to you his oorreseondence with P"al B. PTils. I have 
also included herewith several Rita letters which 
were i.naivprtently omitted with the first ba'ch we 
sent to you. Should you ever find it necessary to 
quote from any of Nr. Leepoll's letters, T preiume 
that this pernission should be 1'ormally obtaine   - from 
his son, Dr. A. S. Leonold, In Berkeley. 
"here is really no urgency that reqtires you to rrturn 
these materials to us in the near future. T am tenta- 
tively selectlnr January 1, 1951 as a reminder f*rte 
which we might autnmattcally ren-v until your Tmesent 
reseereh rolet has been completely written u, and 
the nee  to re-examine the materials is obviovsly psit, 
So lone as you feel there ir5 an,- pottial value in 
yotr keepinr thel-on a loan basis of this ireflo ite 
ty-n, T d* ho-, you will feeol free to dn so. 
                                 Sincerely yours, 
JT; Am                           C ov   tenh J~, Fioke 
                                 Ass~cirate Profesqsor