58 I 



in the protectin 

 deposition of L 

 strengthened thi 



It must be bo 

 can be done by f 

 but perhaps in d 

 retain dust, prai 

 if the supply of : 

 more. It is th( 

 region now cove: 

 though evidence; 

 be found in the ^ 



The thickets ( 

 mon in many p 

 herbaceous plan 

 manner, though 

 greater variatior 

 between the loej 

 thing of the kin 

 eastern Iowa is ; 

 which is less, th< 

 was (and is) fart] 

 its greater fores 

 only the finest i 

 violent winds re 

 the differences ir 

 as indicated by t 

 which exist bet 

 already been em] 



The greatest t 

 be deposited wh' 

 hills, § and would 

 the hills, II thougl 



♦Discussed by the a 



Jour, of Geol., Vol. VII 



+The western part 



stronger southwest wlr 



still a considerable an 



dust. Incidentally it r 



partial or complete drj 



insects and mammals a 



to increase the supply i 



*Proc. Iowa Acad. S 



§Oompare with drif 



llOn the drift nillso 



on the leeward sides, i. 



