ii DIMENSIONAL VARIATIONS 73 



whose influence exerts itself even on plants." That 

 such is the case, and that the influence of environ- 

 ment on dimensions is a very direct one, is amply 

 shown by the results of a change. Horses and oxen 

 become larger when transferred from Brittany to 

 Normandy, while the reverse happens in the reverse 

 case, for when some oxen were sent from Poitou to 

 Brittany, at the third generation the first named race 

 had acquired all the characters of the Breton stock. 



Generally speaking, insular animals are smaller f 

 than their continental congeners. In the Canary 

 Islands the oxen of one of the smallest islands are 

 much smaller than those of the others, although all 

 belong to the same breed, and the horses are also 

 smaller, and the indigenous inhabitants are in the 

 same case, although, belonging to a tall race. It 

 would seem that in Malta elephants were very small 

 fossil elephants of course and that during the 

 Roman period the island was noted for a dwarf breed 

 of dogs, which was named after their birthplace, ac- 

 cording to Strabo. In Corsica also horses and oxen 

 are very small, and Cervus corsicanus> the indigenous 

 deer, is quite reduced in dimensions, although, accord- 

 ing to Polybius, this species was imported from 

 Europe 2,000 years ago, which makes it a descendant 

 of our Cervus elaphus ; and lastly the small dimensions 

 of the Falkland horses imported from Spain in 1764 



