Smithsonian Report, 1962.- Russell 



PLATE 3 



1. Pseudotritia ardua (Koch), a niediuin-sized oribatid mite. \'\-> to 100,000 mites may be 

 found in the top 6 inches of a square yard of soil and some 40,000 in the second 6 inches. 

 (Photo, P. W. Murphy and H, F. Woodward.) 



2. Pergamasus runcatellus Berl., a large oribatid mite. (Photo, P. W. Murphy and H. F. 



Woodward.) 



