Félix Dujardin

Félix Dujardin (5 April 1801 – 8 April 1860) was a French biologist born in Tours. He is remembered for his research of protozoans and other invertebrates.

In 1840 he was appointed professor of geology and mineralogy at the University of Toulouse, and during the following year was a professor of zoology and botany at Rennes. In regard to his educational background, Dujardin was largely self-taught.

Dujardin is largely known for his work with microscopic animal life, and in 1834 proposed that a new group of one-celled organisms be called "Rhizopoda"; meaning "root-foot". The name was later changed to "Protozoa". He refuted naturalist Christian Gottfried Ehrenberg's concept that microscopic organisms are "complete organisms" similar to higher animals. In addition to his studies of microscopic life, he did extensive research of invertebrate groups that included echinoderms, helminths and cnidarians.

In his study of Foraminifera, he observed a seemingly shapeless life substance that he termed "sarcode." This substance was subsequently renamed "protoplasm" by Hugo von Mohl (1805–1872). In 1850, he became the first to document the mushroom bodies, which are crucial components of the nervous system in insects.