THE ICE AGE AND ITS WORK. 43 



occur there also. Tlie comparison will, I think, prove very 

 instructive. 



Spain and Portugal are pre-eminently mountainous countries, 

 there being a succession of distinct ranges and isolated mountain 

 groups from east to west and from north to south ; yet there is 

 not a single valley lake in the whole peninsula, and but very few 

 mountain tarns. Sardinia and Corsica are wholly mountainous, 

 but they do not appear to possess a single valley lake. Nor does 

 the whole range of the Apennines, though there are many large 

 plateau lakes in southern Italy. Farther south we have the lofty 

 Atlas Mountains, but giving rise to no subalpine valley lakes. 

 The innumerable mountains and valleys of Asia Minor have no 

 lakes but those of the plateaus ; neither has the grand range of 

 the Lebanon, a hundred miles long, and giving rise to an abun- 

 dance of rivers. Turning to the peninsula of India, we have the 

 ranges of the Ghauts, eight hundred miles long, the mountain 

 mass of the Neilgherries and that of Ceylon, all without such 

 lakes as we are seeking, though Ceylon has a few plateau lakes in 

 the north. The same phenomenon meets us in South Africa and 

 Madagascar abundance of mountains and rivers, but no valley 

 lakes. In Australia, again, the whole great range of mountains 

 from the uplands of Victoria, through New South Wales and 

 Queensland to the peninsula of Cape York, has not a single true 

 valley lake. Turning now to the New World, we find no valley 

 lakes in the southern Alleghanies, while the grand mountains of 

 Mexico and Central America have a few plateau lakes, but none 

 of the class we are seeking. The extremely mountainous islands 

 of the West Indies Cuba, Hayti, and Jamaica are equally defi- 

 cient. In South America we have on the east the two great 

 mountain systems of Guiana and Brazil, furrowed with valleys 

 and rich in mountain streams, but none of these are adorned with 

 lakes. And, lastly, the grand ranges of the equatorial Andes, for 

 ten degrees on each side of the equator, produce only a few small 

 lakes on the high plateaus, and a few in the great lowland river 

 plains probably the sites of old river channels but no valley 

 lakes in any way comparable with those of Switzerland or even 

 of our own insignificant mountains. 



Having thus roughly surveyed the chief mountain regions of 

 the whole world, we find that true subalpine valley lakes that is, 

 lakes in the lower parts of the valleys descending from mountain 

 ranges or groups, filling up those valleys for a considerable dis- 

 tance, usually very deep, and situated in true rock basins that 

 such lakes as these are absolutely unknown anywhere but in those 

 mountain regions which independent evidence shows to have been 

 subject to enormous and long-continued glaciation. No writer 

 that I am acquainted with has laid sufficient stress on this really 



