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 Achnanthes longipes Ag Achnanthes brevipes Ag Achnanthes subsessilis Kuetz Achnanthes inflata Kuetz Grun Achnanthes coarctata Brb Grun Achnanthes lanceolata Brb Grun Achnanthes danica Floegel Grun lower valve Achnanthes exigua Grun Achnanthes linearis forma curta Smith