Having examined the various theories of the origin of the Loess, which have been current, and found them wanting, I would, with great deference, propose another which has not hitherto been suggested by any geologist, and which offers at least a probable solution of our untractable problem. In previous papers of this series, if we have not proved, as we think we have, that the evidence in favour of the Mammoth and his companions having been suddenly overwhelmed by a great diluvial movement is unanswerable, we claim to have at least shown a very strong á priori probability in favour of such a view.