Bui. 183, Bureau of Plant Industry, U. S. Dept. of Agriculture. 



Plate II. 



a- 



-n 

 ^ 5 



2 Jo 



O I 

 o > 



c 

 m 

 z 

 H 



o 



> 



r 

 r 



CD 



o 

 z 



CD 

 O 



H 

 I 



H 



X 

 m 



O 

 > 



z 

 m 



> rn 



z 



□ a 



