Hart, Henry Chichester (1847–1908), naturalist and literary scholar, was born 29 July 1847 in Glenvar, Raheny, Dublin, second son of Andrew Searle Hart (qv) and Frances Hart (née MacDougall). His father's family was of Co. Donegal origin, and during school holidays there Henry and his two brothers undertook arduous hillwalking expeditions and developed a lifelong enthusiasm for botany and wildlife. He attended Portora Royal School, Enniskillen, and in 1866 entered TCD, where his father was vice-provost. He was awarded a moderatorship in natural and experimental science and graduated (1869) with a BA (hon.). In 1871 he was awarded a diploma in civil engineering. Both during and after his college career, Hart was noted for his physique and athletic prowess, in particular for endurance and speed in walking and mountain climbing: in 1889 he walked about seventy-five miles (120 km) – from Dublin to the summit of Lugnaquilla, the highest mountain in Co. Wicklow, and back – in less than twenty-four hours, and he contributed the Irish sections to Haskett Smith's Climbing in the British Isles (1895). An obituarist noted that lesser mortals should not expect to cover the climbs in the times suggested by Hart. He published a number of papers on the botany of Donegal and other remote areas of Ireland, especially offshore islands and mountain ranges, based on extensive fieldwork, and in 1898 published Flora of the County Donegal. His 1890 paper ‘On the range of flowering plants and ferns of the mountains of Ireland’ established the altitudinal ranges of these plants, presenting new meteorological and other data along with newly discovered locations of alpine and sub-alpine plants. A number of other books and papers on botany, zoology, and ornithology confirmed his reputation for careful observation. In May 1875 he set out as naturalist on HMS Discovery, one of two ships on an ambitious polar expedition; after much hardship and danger they returned in October 1876, without having reached the North Pole. Hart's botanical findings were published in 1880. In 1883 he joined a geological expedition to Palestine and Sinai, under Edward Hull (qv) and H. H. (later Lord) Kitchener (qv), to report on the botany of the area. Hart published his report in the Transactions of the RIA, of which he became a member in 1895. He spent Hilary and Trinity terms in 1887 as a lecturer in QCG, substituting for R. J. Anderson (qv), and in 1888 wrote a pamphlet on animals mentioned in the Bible.
In the latter part of his life Hart turned to literary work. About 1880 he began collecting non-standard words current in Donegal English; his copious and accurate manuscript notes were used by Michael Traynor in his book The English dialect of Donegal (1953), and local plant names and other lore were,somewhat unconventionally, often included in his botanical works. Hart was an acknowledged expert on Elizabethan literature: he edited four Shakespeare plays for the renowned series of Arden editions, also edited Ben Jonson's plays, and wrote on the minor author Robert Greene. As a student, he had published verse in Kottabos. He wrote a history of his family, and had a noted garden at Carraghblagh, Donegal. It was there that he died 7 August 1908, and he was buried in Glenalla, Co. Donegal.
He married first (1887) Edith Donnelly (d. 1901) of Swords, Co. Dublin; they had two daughters. He married secondly (1907) Mary Cheshire. Hart was elected a fellow of the Linnean Society and of the Royal Geographical Society, and an Irish alpine plant species was named in his honour, Saxifraga hartii.