April 08, 2019


April 2019 Viewer's ChoicePhotographer: John H Stetson 
Summary Author: John H Stetson 

The photo above shows a diatom colony, fragilaria, consisting of 32 cells. The cells contain photosynthetic material (green coloration). This sample is about the width of a human hair -- approximately 100 microns in diameter. Note that 40 to 50 percent of the oxygen on Earth is provided by such marine organisms.

Robert Hooke in his book, "Micrographia" (1665) introduced the word, cell to the world. You can get a glimpse of this precious manuscript. However, instead of having to wear white gloves and entering a rare-book collection in a special library, it's possible to visit "Micrographia" online.

Specimen obtained from the Southern Maine Community College dock in South Portland, Maine, and photographed on March 7, 2019.