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648 from preparing an address upon any particular subject. There are two subjects, each of great interest, on which our scientific men are at present greatly divided in opinion. These are the cause and date of glacial action in New Zealand, and the date of the extinction of the Moa. Amongst the papers which have been read here during the past session, there are contributions to the literature of both these controversies.

The evidence which exist of a former great extension of glacial action in this island have formed the subject of several papers, which have been read before you in former years. These papers, however, did not deal, unless perhaps in an incidental manner, with the controverted points; and I am inclined to think, from what I heard of the discussion on the subject at our May and July meetings, that the latter are not quite familiar to a majority of the members of the Society. Captain Hutton's paper "On the Cause of the former great Extension of the Glaciers in New Zealand," would otherwise, probably, have been more fully discussed. Noticing this, I had purposed to take this opportunity of explaining, to the best of my ability, the views which had been put forward by those whose acquaintance with the subject from actual observation entitled their opinions to respect. This has been rendered unnecessary. The seventh volume of the "Transactions of the New Zealand Institute" contains an address by Dr. Knight to the Wellington Philosophical Society, and a paper by Mr. Dobson, "On the Date of the Glacial Period." From these a pretty full idea can be gleaned of the nature of the argument which our leading geologists are carrying on, and in both of them matters are stated with a clearness which I could not hope to emulate. One main point on which there are two schools of opinion is the cause of that great extension of ice which has left its traces in so many localities. Captain Hutton and others attribute it to a considerable elevation of the land above its present level. Dr. Haast, with whom hold amongst ourselves Mr. Thomson and Mr. Beal, believes that a change of climate occurred which brought the snow line down to the sea level, and rendered the whole of the land we now inhabit an icebound region of storms and desolation like that which now exists 2,000 miles to the south of us. A decided majority of those best acquainted with the subject are, in regard to this point, on the side on which Captain Hutton has ranged himself. He denies the existence of adequate evidence that New Zealand passed through any period parallel in its character to that known as the glacial era of Europe and North America, and maintains that all the known phenomena are explainable under the hypothesis of an elevation of the existing land to an extent not necessarily greater than 3,000 feet. With all deference to the able observer who was my immediate predecessor in this chair, I feel bound to say that this hypothesis accords so admirably with all that is known of the tertiary fauna and flora of these islands, and suggests so ready an explanation of the affinities of existing living forms here and in those outlying islands which any considerable elevation of a wide area would unite with New Zealand, that the few facts and the many theoretical conceptions (borrowed from a geological literature which is dominated by deductions from observations made chiefly in the opposite hemisphere), which induce others to refuse to accept it, have no weight with my mind. Geology has been going through its own glacial period of late years, and has been overrun with ice theories which I take leave to think have all left disfiguring striæ on many a fair treatise. All that Captain Hutton has written on this subject, including his admirable paper "On the Geographical Relations of the New Zealand Fauna," gives valuable support to the reaction which has now set in against the widely prevalent theory that the earth was at some not very remote period subjected to cosmical influences which for a time greatly reduced its surface temperature. Conjecture, and the manufacture of hypotheses on this subject, may be said to have reached a