Johnsonia was a publication of the Museum of Comparative Zoology at Harvard University from 1941-1975. It was founded by William J. Clench who named it after Charles W. Johnson who had been one of the men who convinced Clench to pursue the study of molluscs. It was primarily focused on the study of molluscs in the western Atlantic, containing book reviews, guides on where to find various molluscs, drawings of and descriptions of molluscs, and related items.
Johnsonia is also the name of a genus of plants named after Thomas Johnson (d. 1644).