188 DISCUSSIONS IN CLIMATOLOGY. 



In the tufa deposits of Tuscany have been found 

 numbers of plant-remains of indigenous species, com- 

 mingled with others which now no longer grow in 

 Tuscany. Amongst the latter is the Canary laurel, 

 which now flourishes so luxuriantly in the Canary 

 Islands, on the northern slopes of the mountains, at an 

 elevation of from 2000 to 5000 feet above the sea-level 

 — a region, remarks Professor J. Geikie, nearly always 

 enveloped in steaming vapours, and exposed to heavy 

 rains in winter. In that deposit is also found the 

 common laurel, associated with the beech. This is 

 not now the case, as the laurel requires more shade 

 than it can find there at present, while the beech has 

 retreated to the northern flanks of the Appennines to 

 obtain a cooler climate. 



In the tufas of Provence are found groups the same 

 as those which flourish there at present, but com- 

 mingled with them are also the Canary laurel and 

 other plants which are no longer natives of Provence. 

 Saporta directs attention to the fact that species such 

 as the Aleppo pine and the olive, demanding con- 

 siderable summer-heat rather than a moist climate, are 

 entirely wanting in the tufas. 



Similar to those of Provence are the tufas of Mont- 

 pellier. Saporta concludes that when all those species 

 lived together the climate must necessarily have been 

 more equable and humid than at present. In other 

 words, the summers were not so dry and the winters 

 were milder than they are now. 



The deposit near Moret, in the valley of the Seine, 

 is still more remarkable in showing the equable con- 

 dition of climate which then prevailed. The assemblage 

 of plants found there tells a tale, says Professor J. 

 Geikie, which there is no possibility of misreading. 

 " Here," he says, " we have the clearest evidence of a 



