research of the late 1960s and early 1970s. On the initiative of Klaus Günther, who by then held a chair at the Freie Universität Berlin, Hennig was given an honorary doctorate on 4 December 1968; for health reasons, he could not accept this honour in person, and it was presented to him by Günther on 21 March 1969, in Stuttgart. On the initiative of students whom he had lectured on several animal taxa, Hennig was made an honorary professor at the University of Tübingen on 27 February 1970. On the night of 5 November 1976, Hennig died of a heart attack at Ludwigsburg. He had previously repeatedly cancelled lectures with reference to his fading health, and had already had an attack on his journey to Ottawa. He was interred on 10 November at the Bergfriedhof in Tübingen. The dipteran genus Hennigiola is named after him, as is the Evaniid wasp Hyptia hennigi. Legacy The Willi Hennig Society, an organization devoted to the advancement of cladistic principles in systematic biology, was founded in 1981. The society publishes the journal Cladistics. A symposium, Willi Hennig (1913-1976): His Life, Legacy and the Future of Phylogenetic Systematics, was held in London by the Linnean Society of London on 27 November 2013. A symposium volume was published in 2016 by the Systematics Association. Selected works Books: Die Larvenformen der Dipteren, 3 vols., Berlin: Akademie-Verlag, 1948-1952. Grundzüge einer Theorie der phylogenetischen Systematik, Berlin: Deutscher Zentralverlag, 1950. Phylogenetic Systematics, translated by D. Davis and R. Zangerl, Urbana: University of Illinois Press, 1966 (reprinted 1979). Die Stammesgeschichte der Insekten, Frankfurt am Main: Verlag von Waldemar Kramer, 1969. Phylogenetische Systematik, edited by Prof. Dr. Wolfgang Hennig, Berlin and Hamburg: Verlag Paul Parey, 1982. Aufgaben und Probleme stammesgeschichtlicher Forschung, Berlin: Paul Parey, 1984. Articles: "Die Schlangengattung Dendrophis," Zoologischer Anzeiger, vol. 99, 1932, 273-297 (gemeinsam mit W. Meise). "Beziehungen zwischen geographischer Verbreitung und systematischer Gliederung bei einigen Dipterenfamilien: ein Beitrag zum Problem der Gliederung systematischer Kategorien höherer Ordnung," Zoologischer Anzeiger, vol. 116, 1936, 161-175. "Revision der Gattung Draco (Agamidae)," Temminckia: a Journal of Systematic Zoology, vol. 1, 1936, 153-220. "Über einige Gesetzmäßigkeiten der geographischen Variation in der Reptiliengattung Draco L.: „parallele" und konvergente Rassenbildung," Biolog. Zentralblatt, vol. 56, 1936, 549-559. "Die Gattung Rachicerus Walker und ihre Verwandten im Baltischen Bernstein," Zool. Anz., vol. 123, 1938, 33-41. "Probleme der biologischen Systematik," Forschungen und Fortschritte, vol. 21/23, 1947, 276-279. "Kritische Bemerkungen zum phylogenetischen