JOHNSTON, Christopher, physician, born in Baltimore, Maryland, 27 September, 1822. He studied at St. Mary's college, Cincinnati, St. Mary's college, Baltimore, and at the medical department of the University of Maryland, where he was graduated in 1844. He then settled in Baltimore, giving special attention to microscopy, histology, and pathology, in 1858 became lecturer on microscopic anatomy in the Baltimore college of dental surgery, in 1864 professor of anatomy and physiology in the University of Maryland, in 1866 was professor of general, descriptive, and surgical anatomy, and in 1870 filled the chair of surgery, becoming professor emeritus in 1880. His facility as an artist enabled him to illustrate his lectures with water colors and descriptive drawings. He is a member of many scientific and professional societies, and has been president of the Medical and chirurgieal faculty of Maryland, of the Baltimore medical association, and of the Clinical society of Baltimore. He is now (1887) president of the Maryland academy of science, and a constant contributor to professional literature.