I. INTRODUCTION The mechanics of ciliary motion have interested both zoologists and fluid mechanicists for some years. Thus, both Gray (1928) in his book Ciliary Mowement and Prandtl (1952) in his book The Essentials of Fluid Dynamics expressed considerable interest in the fluid mechanics of ciliary movement. Biomechanics is a product of a modem development in scientific research where scientists with different backgrounds (biology and mathematics or physics) pool their knowledge in an attempt to understand a particular problem. Ciliary propulsion is one of the many interesting subjects in the new and rapidly developing field of biomechanics, requiring, in this case, an integration of information from studies in fluid mechanics and physiology. In a recent review article by Jahn & Votta (1972) on the'Locomotion of Protozoa', written for the Annual Review of Fluid Mechanics, the authors summarized, and exposed, the problems they, as biologists, encountered in physically understanding and interpreting the propulsion of some micro-organisms. In the present article