378 Review of Recent Geological Literature. 
marked temperate fauna and flora, which indicate, as the author 
thinks, more than a partial or local retreat of the ice-sheet. The geo- 
graphic distribution of the beds and the presence in them of such 
forms as Elephas antiquus, Cervus elaphus, C. megaceros, and a flora 
comparable to that now existing, lead to the belief that the intergla- 
cial epoch was one of long duration and characterized by climatic con- 
ditions apparently not less temperate than those of the present time. 
Penck, Bohm, and Briickner find evidence of two interglacial epochs, 
and maintain that there have been three distinct and separate epochs 
of glaciation in the Alps. Others, however, as M. Falsan, the eminent 
French glacialist, do not believe in the existence of any interglacial 
epoch, although they readily admit that there were great advances and 
retreats of the icei*during the glacial period. 
Successive marginal moraines, the outermost lying, as in the upper 
part of the Mississippi basin, at a considerable distance north of the 
extreme limits reached by the ice-sheet, are traced across northern 
Germany, and (marking later stages of the glacial recession) around 
the southern coasts of Norway, across the province of Gottland in 
Sweden, passing through the lower ends of lakes Wener and Wetter, 
and in Finland from Hango Head, east-northeasterly, passing north of 
lake Ladoga. 
The author believes that the loess is for the most part of aqueous 
origin, referring its deposition to the flood-waters of glacial times, 
spreading their fine sediment over wide regions of the low grounds, 
in the slack waters of the rivers and in temporary lakes. But he 
remarks that there are ditlerent kinds of loess or loess-like depo-its, 
and that all need not have been formed in the same way. Probably 
some may have been derived, as WahnschafFe has suggested, from the 
denudation of boulder-clay ; and there are still other accumulations, 
as the berg-loess, with its abundant land shells, which no aqueous 
theory will satisfactorily explain. Such loess is apparently the result 
of subaerial action, of rain, frost, and wind acting upon tlie super- 
ficial formations. 
Palaeolithic implements, giving evidence of the early appearance of 
man in Europe, are found, as Prof. Geikie has long maintained, in 
beds of glacial and interglacial age ; and he believes thatnone of these, 
but only neolithic implements, showing increased skill in their manu- 
facture, occur there in postglacial deposits. 
This address closes with the suggestion that when the conditions of 
the glacial period and the causes that gave rise to these have been 
more fully and definitely ascertained, we shall have advanced some 
way toward the better understanding of the climatic conditions of still 
earlier periods, the problem being stated as follows :— "One of the 
chief factors in the present distribution of atmospheric temperature 
and pressure is doubtless the relative position of the great land-and 
water-areas ; and if this be true of the present, it must be true also 
of the past. It would almost seem then as if all one had to do to 
