dodel atlas

A photo of the green alga Volvox globator from the Dodel-Port Atlas, circa 1880. 

Volvox globator exists as a spherical colony of individual single-celled organisms, each with two whip-like appendages called flagella that V. globator uses to propel itself around. The cells are stuck together by thin strands of cytoplasm, allowing them to move in concert to direct the colony’s motions.