Born 20 May 1857 at Bohemia House, Turnham Green, the sixth of the seven sons of George Frederick Collier and his wife Mary Anne Stanley. His father matriculated from Magdalen Hall, Oxford on 15 March 1827 but never graduated in the university; he was an MD of Leyden and was surgeon to the household of HRH the Duke of Clarence, afterwards King William IV. G F Collier's grandfather was (probably) John Collier, MCS. Mayo Collier was educated at Godolphin Grammar School, Hammersmith, at University College, London, and at St Thomas's Hospital. He went to the Dardanelles in 1878 as soon as he had obtained the LSA and was placed in medical charge of the expedition at the end of the Russo-Turkish war. On his return to England he was assistant house physician and house surgeon at St Thomas's Hospital, and in 1881 was elected assistant surgeon to the North-west London Hospital at Haverstock Hill, now the Hampstead General and North-west London Hospital. He became surgeon to the hospital in 1901 in succession to Frederic Durham, FRCS. By that time he had devoted himself to the study of diseases of the throat, nose, and ear. He resigned therefore his office of surgeon, and was appointed surgeon to this department, then newly established at the hospital. In 1902 he was president of the British Laryngological and Rhinological Association. In 1892 he was appointed to the staff of the National Hospital for Diseases of the Heart with the title of consulting surgeon. In 1889 he delivered three lectures as a Hunterian professor at the Royal College of Surgeons upon the physiology of the vascular system, which were published. Early in his career he was assistant demonstrator of anatomy in the medical school of the London Hospital, and was a lieutenant in the East London Royal Engineers (Volunteers). He married on 27 March 1901 Florence, elder daughter of Dr Spooner Hart of Calcutta and Brocklesby, Corona, Australia, but had no children. He died at Kearsney Abbey, Kent on 20 September 1931 and was buried in Brookwood cemetery. Publications:- Removal of the tongue and floor of the mouth by a new method. *Lancet*, 1885, 2, 340. Functions of the sinus of Valsalva and auricular appendages. *Proc Royal Society*, 1887, 42, 469. *On the physiology of the vascular system*. London, 1889. *An address on the present position of nasal surgery and the causation of deflection & of the nasal septum*. Brit Laryng and Rhinolog Association London, 1892. *Chronic progressive deafness its causation and treatment*. London, 1905. *The throat and nose and their diseases*, with Lennox Browne. London, 1886.