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the Verein zur Verbreitung naturwissenschaftlicher Kenntnisse in Vienna, now in its thirty-third year. The essays may be had separately, and a table of contents of the thirty odd volumes may be procured from the publisher, Hölzel, for a nominal price; from this one may select such numbers as he wishes. Recent volumes contain articles by Suess, Ueber die Structur Europas, from which the geological traveler may gain a breadth of view that will greatly profit him; by Penk, on Das Oesterreichische Alpenvorland, and Die Donau (Danube), from which more local views may be gathered of equal value in closer studies. Dr. Böhm's essay is a well-argued presentation of the belief that even the greater Swiss lakes, as well as nearly all the smaller ones, are the result of glacial erosion. He justly emphasizes the moderate proportion of depth to length in even the deepest of the marginal lakes; and the location of these lakes with respect to the greater glacier which formerly emerged from the Alpine valleys on the Piedmont districts. Even in those valleys where no marginal lakes now exist, as in the valleys of the Lech, Inn, Salzach, and others, rivers emerging from the northeastern Alps, there have recently been lakes, but their basins are now filled and drained by the active streams that traverse them. The high level lakes, held in rock basins and enclosed by mountain cirques (Karen), are with even more confidence ascribed to glacial action. Many of the smaller lakes have been extinguished already since the glacial period. In the Tyrol, no less than 118 lakes recorded on the maps of the last century, are now drained. In this relation, the Alpine valleys seemed to have advanced further towards recovery from the glacial accident to which they have been subjected than the Norwegian streams; for in Norway, many a river is still only a string of lakes. It is notable that drumlins are not mentioned by Dr. Böhm as characteristic products of glacial action; hence we must infer that they are seldom seen in Continental Europe.