Euglena is a genus of single-celled, flagellate eukaryotes. It is the best-known and most widely studied member of the class Euglenoidea, a diverse group containing some 54 genera and at least 200 spe
Euglena sociabilis 433143410
Euglena ehrenbergii 484934895
Cercaria viridis (= E. viridis) from O.F. Müller's Animalcula Infusoria. 1786
Euglena from Félix Dujardin's Histoire Naturelle des Zoophytes, 1841
Protozoa are a polyphyletic group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic debris. Historically, protozoans wer
Euglena
…the source, permitting the Euglena to find the light and move toward it (a process known as phototaxis). Euglena lacks a cell wall. Instead, it has a pellicle made up of a protein layer supported by a substructure of microtubules, arranged in strips spiraling around the cell. The action of these pellicle…
Clockwise from top left: Blepharisma japonicum, a ciliate; Giardia muris, a parasitic flagellate; Centropyxis aculeata, a testate (shelled) amoeba; Peridinium willei, a dinoflagellate; Chaos carolinense, a naked amoebozoan; Desmarella moniliformis, a choanoflagellate
Class Protozoa, order Infusoria, family Monades by Georg August Goldfuss, c. 1844
John Hogg's illustration of the Four Kingdoms of Nature, showing "Primigenal" as a greenish haze at the base of the Animals and Plants, 1860
Frederick Chapman's The foraminifera: an introduction to the study of the protozoa (1902)