Harry Bolus, businessman and botanist, was the son of Joseph Bolus and his wife Anne Gillham. He showed an interest in science, and particularly in natural history, from an early age. In March 1850 he came to South Africa as an apprentice to William Kensit, a merchant of Grahamstown. Towards the end of that year the Eighth Frontier War broke out and he had to go on active service. Two years later he left Kensit's business and became a bookkeeper in a firm in Port Elizabeth. After a brief visit to England in 1855 he settled in Graaff-Reinet later that year and remained there for 19 years, playing a prominent role in the intellectual and business affairs of the town. Among others he was secretary of the local immigration board, secretary of the amateur theatrical club, on the committee of the Graaff-Reinet Agricultural Society, started a general dealer's business with his brother Walter in 1858, became secretary of the Graaff-Reinet board of executors in 1863, and for ten years was secretary of the Midland Fire Assurance and Trust Company, which he helped to establish in 1864. In 1857 he married Sophia Kensit (1829-1914), sister of his former employer.
Bolus formed a friendship with Francis Guthrie*, who arrived in 1861 as professor of mathematics at the newly established Graaff-Reinet College, and attended the latter's short course of public lectures on botany in 1862. Three years later, after the death of his eldest son, Bolus sought solace in the study of botany and developed it into his life-long passion. All his botanical work was thorough, accurate, and showed meticulous attention to detail. He started his herbarium in April 1865 and commenced a life-long correspondence with Sir Joseph Hooker* and others at Kew Gardens, with W.H. Harvey* in Dublin, and with P. MacOwan*, who was then in Grahamstown. He served on the committee of the Grahamstown Botanic Garden and in 1866 joined MacOwan as the second secretary of the latter's South African Botanical Exchange Society. In 1869 he sent specimens of the curious root parasite on Euphorbia species, Hydnora africana, to the Albany Natural History Society, to be discussed by MacOwan. His first botanical publication, "Botany at the Cape", was a review of the second edition of Harvey's Genera of south African plants, and appeared in the South African Magazine in 1869. In this article Bolus described the state of botanical exploration at the Cape and the lines along which botanical investigation should proceed. He also stated his willingness to correspond with any person interested in natural history. This willingness resulted in an extensive correspondence which he maintained throughout his life, encouraging and advising many isolated collectors and naming their plants. Among those who received his support were F.R.R. Schlechter*, N.S. Pillans*, and C.F.L. Leipoldt*.
Bolus originally collected plants around Graaff-Reinet and adjacent regions. In the Eastern Cape he collected with H.G. Flanagan* and E.E. Galpin*. He went on a collecting trip to Namaqualand in 1883 and in 1886 travelled from Maputo to Barberton and back to Cape Town via Pretoria. In 1893-1894 he collected in the Free State with Flanagan and travelled to Mount-aux-Sources. With MacOwan and A.A. Bodkin* he collected around Clanwilliam and Wupperthal in 1897. He visited the Transvaal again in 1904 and in 1905-1906. During the latter visit he also went to Swaziland, where he collected at Dalriach (just north of Mbabane), and in the Middleveld.
In December 1874 Bolus moved to Cape Town and again entered into partnership with his brother Walter, this time starting the first firm of stockbrokers in Cape Town. Walter soon returned to Britain, leaving Harry in charge of the business until he retired in 1895. He lived first at Rosebank, then Rondebosch, and from 1887 to 1911 in Kenilworth. During these years he did most of his collecting in the south-western Cape, often accompanied by MacOwan, Guthrie, Bodkin, or his daughter Ethel, who died in 1890. With Guthrie he left on a visit to Europe in April 1876, at the end of which he paid the first of a series of ten or more visits to Kew Gardens, taking numerous specimens with him for comparison. Through these visits he formed close personal contacts with British taxonomists. Returning from his first visit the Windsor Castle struck a rock near Dassen Island, resulting in the loss of all his specimens and most of his notes. Undeterred he started building up his herbarium again.
Soon thereafter Bolus developed a life-long special interest in orchids and, while at Kew Gardens in 1881, initiated his studies of this group by preparing a "List of published species of Cape orchids" which appeared in the Journal of the Linnean Society, Botany in 1882. His "Notes on some Cape orchids" appeared in the same volume. In 1888 he published "The orchids of the Cape Peninsula" in the Transactions of the South African Philosophical Society (Vol. 5, pp. 75-201), with descriptions of 117 species and illustrated with 36 partly coloured plates prepared by himself. This was followed in 1893 by Volume 1, Part 1 of his Icones Orchidearum Austro-Africanarum extratropicarum, with 50 plates. Volume 1, Part 2 appeared in 1896 and Volume 2, with 100 plates, in 1911. Volume 3 was completed after his death and published in 1913 by Miss H.M.L. Kensit*, his assistant and grand-niece by marriage.
Another matter to which Harry Bolus early on devoted his attention was the geographical distribution of plants. Already in 1875 he translated a treatise on this topic by Professor Ernst Meyer of the University of Koenigsberg, Germany, based on the collections of J.F. Drege*. The work was published as "On the geographical distribution of plants in South Africa" in the Cape Monthly Magazine (1873-1874) and also as a monograph (Cape Town, 1875, 61p). In 1886 he compiled a "Sketch of the flora of South Africa" for John Noble's* Official handbook of the Cape of Good Hope, in which he described the different botanical regions of South Africa and pointed out its great diversity of species. This article was positively reviewed by Sir Joseph Hooker and later formed the basis of Bolus's "Sketch of the floral regions of South Africa" in W. Flint* and J.D.F. Gilchrist* (eds), Science in South Africa (1905).
In 1882 Bolus was co-author, with MacOwan, of an historically important paper, the "Catalogue of printed books and papers relating to South Africa. Part I. Botany", which was published in the Transactions of the South African Philosophical Society (Vol. 2, pp.115-187). In 1889 he made a large contribution of plants to the Natal Herbarium, his donations eventually totalling nearly 1300 specimens. He also presented many rare plants to the Albany Museum in Grahamstown. In collaboration with his old friend Guthrie, Bolus started in 1894 with the elaboration of the heaths for the Flora Capensis. Continuing alone after Guthrie's death in 1899, he described 469 species of Erica endemic in South Africa. His descriptions were completed in 1905 and with descriptions of other members of the family by N.E. Brown* appeared in Volume 4 of the Flora Capensis. In the prefaces to several volumes of the Flora Capensis the editor, W.T. Thiselton-Dyer* furthermore thanked him for his donations of numerous specimens to Kew Gardens, the loan of others, and his valuable research on the geographical distribution of South African plants.
Another venture by Bolus involved collaboration with Captain A.H. Wolley-Dod*, with whom he published the first attempt to record the flora of a particular region in South Africa, "A list of the flowering plants and ferns of the Cape Peninsula" in the Transactions of the South African Philosophical Society (1903, Vol. 14, pp. 207-373). Many of his other papers were published in the Journal of the Linnaean Society and the Transacations of the South African Philosophical Society over the years. Through these and other contributions he played an important role in the establishment of botany as a science in South Africa.
Bolus became a Fellow of the Linnaean Society in 1873. He was a founding member of the South African Philosophical Society and its first treasurer (1877-1881), served on its council for 30 years, and was president in 1886-1887. When the society became the Royal Society of South Africa in 1908 he became one of its original Fellows and served as its first treasurer. In 1895 Volume 121 of Curtis's Botanical Magazine was dedicated to him. The University of the Cape of Good Hope awarded him an honorary Doctor of Science (DSc) degree in 1903. He joined the South African Association for the Advancement of Science in 1903 and received its South Africa Medal and Grant in 1909. Five plant genera, Bolusia, Bolusafra, Neobolusia, Bolusanthus, and Bolussiella were named after him.
Bolus was widely read in English prose and poetry and had a keen appreciation of art. He was strongly convinced of the value of education for the improvement and welfare of mankind and made several contributions to the advancement of higher education. For example, he provided financial assistance for the foundation of a chair of Botany in the South African College in 1902 (it was designated the Harry Bolus Chair of Botany in 1917) and from 1908 to 1910 served as a member of he College council. His herbarium and library, the latter a very fine collection of botanical Africana, were donated to the College and provision made in his will to finance their maintenance and extension. He also bequeathed his house to the college and provided an endowment to finance scholarships for needy students. From 1897 until just before his death he served on the board of directors of the South African Library. He was appointed by government as a member of the Vine Diseases Commission of 1880 and as a trustee of the South African Museum from 1906 to 1909. He was also a director of the Mutual Life Assurance Society of the Cape of Good Hope, and of the Colonial Orphan Chamber, from 1882 onwards.
Bolus left South Africa for England in April 1911 and died soon after his arrival there. He has been described as a man of strict integrity and unflinching candour, retiring by nature and inclined to depreciate his own achievements.