38 THE WOELD OF LIFE 



the original authorities, and he has kindly brought them 

 up to date as far as possible, so that they may be fairly com- 

 parable.) 



Although very unequal in extent, the various Swiss 

 cantons, which form the bulk of this table, are remarkably 

 similar in their botanical riches, the smallest, most northerly, 

 and least alpine (Schaffhausen) having more than two-thirds 

 the number of species of the Valais, the most southerly, 

 nearly the largest, and the most alpine, the main chain of 

 the Alps for nearly 100 miles forming its southern boundary, 

 and the Bernese Alps its northern, But Schaffhausen geo- 

 graphically connects eastern France wdth western Germany, 

 and partakes of the rich flora of both countries. This table 

 of the Swiss cantons is also very interesting in showing us 

 that alpine floras are really no richer in species than those 

 of the lowlands, if we compare approximately equal areas. 

 A remarkable illustration of this is the comparison of the 

 Ofengebietes, a district including snowy peaks, forests, and 

 lowland meadows, having almost exactly the same number 

 of species as an equal area near Strasburg, or one around 

 the town of ITertford ! Switzerland, thouirh so verv unlike 

 Great Britain in situation, climate, and physical conditions 

 generally, yet reproduces in its cantons that curious uni- 

 formity in species-production that we found to be the case 

 in our counties. But as Switzerland, though only one-fifth 

 of our area, has a gTeater number of species by one-third, 

 that superiority is, as a rule, reproduced in its subdivisions. 

 Susa, in Piedmont, wdth its fertile valleys and snowy Alps, 

 has by far the richest flora of the whole series, due to its 

 w^arm climate, variety of surface, and complete shelter from 

 the north. Mytilene, the farthest south, has doubtless been 

 impoverished botanically by its large population and extensive 

 fruit culture. 



It is, I think, clear that, other things being equal, an 

 alpine flora is not at all richer than a lowland one ; but, as 

 we shall see further on, there are indications that the high 



