on the Rocks in the Environs of Edinburgh. 315 



formed from the glaciers. Wheresoever high summits and 

 escarpments prevail, there the blocks, stones, and fragments 

 which are detached, fall upon the ice and form long dikes, 

 the necessary result of the progression of the glacier. But, 

 on the other hand, when a glacier is overtopped only by a 

 small number of peaks, and those of small elevation, then 

 few or no fragments fall upon its surface, and no moraines 

 are formed, either lateral or terminal. Thus, at Spitzber- 

 gen, where the mountains are, as it were, buried in the ice, 

 where you see only the most elevated peaks in the centre 

 of the island, the moraines are reduced to very small dimen- 

 sions. In Scotland, at the time of the greatest extension of 

 the glaciers, it was very much the same ; and I am con- 

 vinced that very few summits surpassed the peaks of the 

 ice. When, from the hills which bound Gare Loch, we ob- 

 serve the high mountains which divide that loch from Loch 

 Lomond, we are surprised to see that they are rounded and 

 moutonnee to their very top. Now, the invasion of the en- 

 virons of Edinburgh by the glaciers evidently corresponded 

 to the maximum of their extension, in other words, to the 

 epoch when the mountains themselves were covered under a 

 mantle of ice. Let us not be surprised, then, when we do 

 not find true moraines in the neighbourhood of Edinburgh ; 

 but only striated pebbles and erratic boulders at a great dis- 

 tance from each other : this peculiarity finds its explanation 

 in the limited elevation of the mountains in so northern a 

 region. When we consider that at this epoch the Yosges were 

 equally covered over, and the valleys of the Pyrenees were 

 occupied with glaciers, we can understand that Scotland then 

 represented exactly the present existing state of Spitzbergen. 



Zoological Proofs of the Ancient Existence of Marine Glaciers 

 in Scotland* 

 Mr Smith of Jordanhill has shewn that, during the 

 epoch of extreme cold, the maritime Fauna of Scot- 



* Many years ago I received from Mr Smith a collection of the Clyde fossils. 

 I proposed to him sending them to Mr Deshayes of Paris, the celebrated natu- 

 ralist. This was done, and in due time a named catalogue of them was returned 

 to me, with the iuiimation that some of the shells were arctic. — Ed. Phil. Jour. 



