9520607 Rowe This research involves determination of the evolutionary relationships among fossil marine reptiles. Morphological, morphometric and biogeographical evidence will be evaluated. The proposed research will yield significant new phylogenetic information regarding the interrelationships of members of this reptilian family. In addition the study will provide an evaluation of different methods for recovery of the best estimate of amniote phylogeny. A final consideration will be the power of a phylogemy to predict morphological changes.