Lang was born at Kurnal, India the second son of Edward Tickle Lang and Hebe, the daughter of John Venn Prior. At the age of 1, the family returned to England from the Punjab region of India. Lang's father was a civil servant, who had been working on the Jumna Canal in the Punjab.
In 1902 he started as an assistant in the Geology Department of the British Museum in charge of Protozoa, Coelenterates, Sponges and Polyzoa. During World War I he was made curator of mosquitos and produced in 1920 "A Handbook on British mosquitos". After the war he returned to the Geology Department and in 1928 became Keeper of Geology in succession to F. A. Bather. Lang was elected as a Fellow of the Royal Society in May 1929. His candidacy citation read: "Distinguished for his knowledge of palaeontology; has applied evolutionary principles to the systematic arrangement of fossil polyzoa and corals, studying the recapitulation of ancestral characters in the post-embryonic growth-stages of compound as well as simple organisms, e.g., 'Brit Mus Catalogue Fossil Bryozoa', 'The Pelmatoporinae'. Lang elucidated in detail the faunal and stratigraphical succession of the Lias along the Dorset coast, with special relation to ammonites. He was a proponent of the theory oforthogenesis, believing that several lineages of cribrimorph cheilostome bryozoans evolved progressively thicker and more elaborate skeletal structures which eventually became maladaptive, driving the lineage to extinction. By extending the study of existing British species of mosquitoes to their four larval stages, previously ill-known, he tested the relationships already inferred from imaginal characters.
Later life
Lang mentored many students, who came to use the facilities of the British Museum. He retired from the British Museum in 1938 and moved to Charmouth, Dorset, where he had holidayed from an early age. In 1940, Lang, Stanley Smith and H. Dighton Thomas published the "Index to palaeozoic coral genera". In his retirement Lang wrote several articles about Mary Anning, the fossil collector. He also published on the geology and palaeontology of the Dorset coast around Charmouth. In all, he published over 130 papers. He was president of the Dorset Natural History and Archaeological Society from 1938 to 1940 and member of its council from 1956 to 1966. He was well liked and respected, and his letters to colleagues and students, including Dorothy Hill, demonstrate the respect and affection with which he and his work was held.
Personal life
Lang married Georgiana Dixon in 1908; they had a son, W. Geoffrey Lang and a daughter, J. Brenda Lang. He died in 1966 and was survived by his wife and children.
