This volume of essays is meant as a tribute to Alistair Crombie by some of those who have studied with him. The occasion of its publication is his seven­ tieth birthday - 4 November 1985. Its contents are a reflection - or so it is hoped - of his own interests, and they indicate at the same time his influence on subjects he has pursued for some forty years. Born in Brisbane, Australia, Alistair Cameron Crombie took a first degree in zoology at the University of Melbourne in 1938, after which he moved to Je­ sus College, Cambridge. There he took a doctorate in the same subject (with a dissertation on population dynamics - foreshadowing a later interest in the history of Darwinism) in 1942. By this time he had taken up a research position with the Ministry of Agriculture and Fisheries in the Cambridge Zoological La­ boratory, a position he left in 1946, when he moved to a lectureship in the his­ tory and philosophy of science at University College, London. H. G. Andrewa­ ka and L. C. Birch, in a survey of the history of insect ecology (R. F. Smith, et al. , History of Entomology, 1973), recognise the importance of the works of Crombie (with which they couple the earlier work of Gause) as the principal sti­ mulus for the great interest taken in interspecific competition in the mid 194Os.