The Glacial Period and the Irish Fauna

Abstract

MR. LAMPLUGH assumes (NATURE, January 13, p. 245) the correctness of the view that during the Glacial Period the basin of the Irish Sea was filled with an ice-sheet, and argues that my “interesting speculations” on the origin of the Irish fauna, in so far as they are based upon assumptions as to the glacial conditions of the Irish Sea, will therefore possibly not meet with much acceptance among geologists. That the Irish Sea, however, was filled with an ice-sheet during the Glacial Period is certainly not universally accepted among geologists. I think also, that it would have been more advantageous to us to hear Mr. Lamplugh's remarks, after having read in full my paper dealing with the origin of the Irish fauna, instead of the short abstract in NATURE. He would then have observed that I particularly avoided basing assumptions as to the origin of the Irish fauna on the glacial conditions of the Irish Sea. It has been rather too much the practice among some geologists of late, not only to assume the correctness of their theories as to the nature of the Glacial Period, but also to base thereon the probable course of events of the migrations of animals and plants. I have attempted, with a view to arriving at a more satisfactory conclusion on the origin of the British fauna, to found my deductions almost entirely on the presence in or absence from the British Islands of continental species. These conclusions are at variance with the views held by the, what we might call, extreme Glacial school of geologists.