This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Diatomaceae of Philadelphia Plate . follows PLATE Fig Biddulphia biddulphiana Smith Biddulphia rhombus Ehr Wm Sm Biddulphia granulata Roper Biddulphia turgida Ehr Wm Sm Biddulphia smithii Ralfs Biddulphia lvis Ehr Biddulphia lvis Ehr Sporangial frustules diam Eunotogramma lve Grun org Charles Sumner Boyer PDoldauto