JEFFRIES, Benjamin Joy, physician, born in Boston, Massachusetts, 26 March, 1833. He was graduated at Harvard in 1854, and in the medical department there in 1857, and, after two years' study in Europe, settled in Boston, making a specialty of diseases of the aye and skin. He is ophthalmic surgeon to the Massachusetts eye and ear infirmary, to Carney hospital, and to the New England hospital for women and children, and is a member of various medical societies. Dr. Jeffries has taken much interest in the subject of color-blindness, and has tested the eyes of thousands of people in various parts of the country. His examinations, reported in his manual on "Color-Blindness, its Dangers, and its Detection" (Boston, 1873), shows that, in the United States, as elsewhere, four percent of males and one fourth of one per cent of females have defective color-sense; their results have also brought about a systematic examination of the form and color-sense of railroad employes and pilots, and the gradual establishment of laws of control of these, he has published "The Eye in Health and Disease" (Boston, 1871): "Animal and Vegetable Parasites of the Human Hair and Skin," a Boylston prize essay on "Diseases of the Skin" (1872); a prize essay on "The Eye," Massachusetts medical society publication: and "Enucleation of the Eyeball," "Reports of Cataract Operations," and articles on dangers of defective vision, and the necessity for legislative enactment.