The interesting paper on “The Connection of the Glacial Period with Oscillation of the Land,” by Dr. Holst, while reinforcing the quite probable theory that areas loaded with glacial ice sink under the burden, and after the ice has been thawed rise again, goes out of its way to deny the existence of Interglacial periods, probably with the idea that there was only one important sinking and rising in the Pleistocene, and hence no opportunity for Interglacial times. However that may be in Sweden, the evidence in favour of at least one important Interglacial period in North America is too strong to be set aside for any mere theory.