Dr. G. Fryer is distinguished for his work on the fishes of the Great Lakes of Africa and on the small Crustacea, in which he has correlated anatomical structure with habits and ecological requirements in great detail. He has made a notable contribution to molluscan knowledge by his study of development in mutilid (bivalve) molluscs with first description of the unique haustorial larva. His most important advances have been made on the feeding mechanisms, habits, ecology and evolution of the many groups of Cladocera (and other Crustacea) where he has applied engineering principles to microanatomy in a manner never yet equalled, and which is throwing most important light on the modes of evolution and relationships of these animals.