IN NATURE for May 2 Captain Oliver advocates the theory that dolmens are merely the skeletons of original chambered tumuli. This, I think, scarcely agrees with the fact to be observed in the principal dolmens and tumuli of Finistere. In most cases in that department the dolmens occupy situations in every respect similar to those in which the tumuli are found, so that meteorological, and, indeed, every other but human agencies, must have affected both in the same manner and degree. Notwithstanding this, the dolmens are invariably bare, and the kists are as constantly covered—there are no signs of even incipient degradation and denudation in the latter, and none of former covering in the first. It would be unwarrantable to suppose that had the dolmens been uncovered by human beings, no vestiges of the mounds would remain, or that, this perfect and unaccountable removal of material being allowed, the skeleton, i.e., the part containing the most useful stones, should be left unscathed.