Illustration of mollusk. Acephala. - Muscheln, 1 print : lithograph, 1904. Ernst Haeckel 1834? 1919 German biologist, naturalist, philosopher, physician, professor, and artist who discovered, described and named thousands of new species, mapped a genealogical tree relating all life forms, and coined many terms in biology, including anthropogeny, ecology, phylum, phylogeny, stem cell, and Protista.