If truth is elicited by the conflict of opinion, we ought to arrive at a right conclusion as to the physical history of the English Trias. Unfortunately, however, some of the hypotheses propounded result, as it seems to me, from dwelling too much on certain minor difficulties, or limiting the view to one group of facts, while others not less important are excluded. From these objections Mr. Mellard Reade's interesting communication, printed in the GEOL. MAG. for last December, does not appear to me exempt.