William West Sr. FLS (22 February 1848 in Leeds – 14 May 1914 in Bradford) was an English botanist, particularly noted for his studies of freshwater algae. He had sons named William (1875–1901) and George Stephen (1876–1919), both also botanists.
West, W. 1892. Algae of the English Lake District. J. Roy. Microscop. Soc. pp. 713–48.West, W. 1892. A contribution to the freshwater algae of west Ireland. Journal of the Linnean Society, Botany 29: 103 - 216.West, W. and West G.S. 1896. On some new and interesting freshwater algae. J. Roy. Microscop. Soc. 16 149 et seqWest, W. 1912. Clare Island Survey: Fresh-water algae with a supplement of marine diatoms. Proceedings of the Royal Irish Academy 31 (1911–15) section 1, part 6.West, W. and West G.S. 1897. Welwitsch's African freshwater algae. J. of Bot. 35: 1 et seq.West, W. and West, G.S. 1902. A contribution to the freshwater algae of the north of Ireland. Transactions of the Royal Irish Academy 32 (1): 1 - 100.West, W. and West, G.S. 1903. Notes on freshwater Algae. III. Journ. bot. pp. 33 et seq.West, W. and West, G.S. 1904, 1905, 1908, 1912. A monograph of the British Desmidiaceae. Volumes I - IV. London. The Ray Society.West, W. and West, G.S. 1906. A comparative study of the plankton of some Irish Lakes. Transactions of the Royal Irish Academy 33B: 70 - 116.West, W. and West, G.S. 1909. The British freshwater phytoplankton, with special reference to the desmid-plankton and the distribution of British desmids. Proceedings of the Royal Society 81B, 165 - 206.West, W., West, G.S. and Carter, N. 1923 A monograph of the British Desmidiacese. Volume V. London. The Ray Society. 