Born at Clovelly, in Devonshire, the youngest of the three sons of Colonel De Morgan of the Indian Army, Augustus, the celebrated mathematician, being his elder brother. He was educated at University College, London, and at the Middlesex Hospital, where he became Assistant Surgeon in 1842, and full Surgeon on the retirement of Edward William Tuson (qv). In those days members of the staff had to lecture on many subjects, and De Morgan lectured on forensic medicine, on anatomy, on physiology, and he became the sole lecturer on surgery on the retirement of Alexander Shaw (qv). He contributed, in conjunction with John Tomes (qv), a paper to the Royal Society on the "Development of Bone" which gained for him the Fellowship of the Royal Society. He was a devoted friend of John Graham Lough (1806-1876), the sculptor, who married a sister of Sir James Paget. After sitting up with him through the night, he returned home in the cold of an early morning and died on April 12th, 1876, four days after his friend. A lithograph of him, dated 1876, and a photograph are in the College Collections. The male line of the family ended with Campbell William De Morgan, grandnephew of the above, who died on January 27th, 1924 (*Lancet*, 1924, February 23rd). Publications: "Observations on the Structure and Development of Bone" (with JOHN TOMES) - *Philosophical Trans.*, 1853, cxliii, 109. "Erysipelas" in Holmes's *System of Surgery*, 1860. *Origin of Cancer*, 1872.