Smithsonian Report. 1936.— Conger 



Plate 10 



I^Wb 



Florida diatomaceou.s earth (center) coiitainiua iiumerotLs small filelike diatoms as pictured above and 

 below, Eunotia zygodon Ehr. and var., very useful for polishing silver. Center, X 100; upper and lower, 

 X 600. 



