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IOWA ACADEMY OF SCIENCE Vol. XXVI, 19iy 



iiredo sori. Plants observed at Ames and Des Moines beginning 

 December 9, 16, 23, 30, in 1918, and January 4, 11, 18, 25, February 

 1, 8, 15, 22, March 1, 8, 15, 22 and 29, April 5, 12 and 19 showed no 

 traces of uredo spores although the old stems in some cases were 

 covered with teleuto sori of the fall. It is certain that by the cold 

 previous to November 8, when much of the vegetation of delicate 

 plants was killed, leaving volunteer plants of wild oats and wheat, 



Fig. 4 5. — Rust and Barberry, Scales Mound, Illinois. +z=Barberry. (C. M. King.) 



the squirrel tail was uninjured or but slightly injured. Though wild 

 rye, Ely)iius virgiiiiciis, had considerable leaf rus.t and Puccinia mon- 

 tanensis and P. ruhigo-vcra were common on the leaf of squirrel 

 tail, no further development of Puccinia grauiinis occurred on oats, 

 wheat, ({uack grass, timothy or squirrel tail. 



Hordeum cccspitosum (Scribner) is a grass of western and north- 

 ern Wyoming, northern Colorado and central Utah. It was found, 

 as a waif, near Mitchell, Soutb Dakota, and had some rust on it. 



