As a result of an investigation covering the Midland area, and especially from a study of the Upper Keuper of Leicestershire, the author, who has been aided in this research by a grant from the Government Grant Committee of the Royal Society, has arrived at the conclusion that, in so far as Great Britain is concerned, the Trias was laid down under delta conditions, during which, as in the Nile area to-day, æolian action took place, but was not responsible for deposition except locally on a small scale, and following the prevalent wind course.