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THE MICROSCOPE AND ITS REVELATIONS, 



PLATE I. 



VARIOUS FORMS OP DIATOMACE.E. 



Fig. 1. Actinocyclus Ralfsii. 



2. Asterolampra concinna. 



3. Helioptlta (as seen with black-ground illumination). 



4. Asternmphalus Brookeii. 



5. Aulacod iscus Oreganus, 



