The circular diatom in the center of the arrangement is 90 microns in diameter. This image contains fifty diatoms of various shapes which have been assembled into the shape of a star. The star-shaped diatom in the center of the arrangement is 70 microns across. They are so small that they must be studied with an electron microscope. We will look at photos in lab.
Organism is spherical to sub- spherical and covered by circular plates called coccoliths.
Coccoliths may resemble a button or a daisy with petal-like ornamentation around the edge. Useful in biostratigraphy and paleoenvironment interpretation. Dinoflagellates Images courtesy of Lucy Edwards, U.S. Geological Survey. Cambrian to Recent. Ostracodes in Late Triassic non-marine shale, North Carolina.