Notes on Early Mesozoic Theropods contains two papers on the poorly studied late Triassic and early Jurassic theropod dinosaur fauna of North America. The author discusses the evidence that has been used to support cannibalism hypothesis in the late Triassic dinosaur Coelophysis, and presents new evidence that disproves this commonly cited hypothesis. In the second paper, the author names a new genus and species of theropod dinosaur from the early Jurassic Kayenta Formation of Arizona. The new taxon represents the oldest yet-known example of a Tetanuran theropod in North America. For those interested in the paleontological history of the American southwest or the early evolutionary history of this interesting clade of dinosaurs, Notes on Early Mesozoic Theropods adds more information to the emerging picture of life in the southwest over 190 million years ago.