Savage, R. J. G. (Department of Geology, University of Bristol, University Walk, Bristol, England, BS8 1TR) 1976. Review of early Sirenia. Syst. Zool. 25:344–351.—Advances in our knowledge of fossil sirenians over the past four decades are reviewed and a cladistic phylogeny of the order presented. Salient features of the recently re-prepared type skull of the most primitive known sirenian, Prorastomus (middle Eocene, Jamaica), are summarised.