wherein a cooling, perhaps sudden, but in any case very marked, showed itself and then disappeared.
At this moment, a part of the globe at least, and Europe in particular, was much colder than it is now. We have proof of this in the glaciers of the Alps. Instead of stopping at the place where they do now, these glaciers filled most of the Swiss valleys, descending even in the valley of the Rhone; and from one end to the other of these valleys enormous blocks of rock were transported by the glaciers, and
| Fig. 1. | Fig. 2. |
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| Arrow-shaped Flint Implements. | |
left on the spot. It is these which now constitute what we call erratic blocks.
During the Quaternary epoch, there lived in France very different animals from those which we find now. Among them I may refer to the great cave-bears, which were remarkable for their size and for their bulging foreheads. I will also mention the hyena. You know that now we have no hyenas, and that they are only found in countries much warmer than France. To the preceding species I will add the rhinoceros. I call attention particularly to an elephant, of which this is the picture (Fig. 1), and which we call the mammoth. This elephant,
