Chap. XXVI II. 



CONCLUDING REMARKS. 



427 



between the fruits produced by the varieties of the same fruit- 

 tree, between the flowers of the varieties in our flower-garden, 

 between the seeds, roots, or leaves of our culinary and agricul- 

 tural plants, in comparison with the other and not valued parts 

 of the same plants. Striking evidence of a different kind is 

 afforded by the fact ascertained by Oswald Heer, 8 namely, that 

 the seeds of a large number of plants, — wheat, barley, oats, peas, 

 beans, lentils, poppies, — cultivated for their seed by the ancient 

 Lake-inhabitants of Switzerland, were all smaller than the seeds 

 of our existing varieties. Butimeyer has shown that the sheep 

 and cattle which were kept by the earlier Lake-inhabitants were 

 likewise smaller than our present breeds. In the middens of 

 Denmark, the earliest dog of which the remains have been 

 found was the weakest ; this was succeeded during the Bronze 

 age by a stronger kind, and this again during the Iron age by 

 one still stronger. The sheep of Denmark during the Bronze 

 period had extraordinarily slender limbs, and the horse was 

 smaller than our present animal. 9 No doubt in these cases the 

 new and larger breeds were generally introduced from foreign 

 lands by the immigration of new hordes of men. But it is not 

 probable that each larger breed, which in the course of time 

 supplanted a previous and smaller breed, was the descendant 

 of a distinct and larger species; it is far more probable that 

 the domestic races of our various animals were gradually im- 

 proved in different parts of the great Europaeo-Asiatic conti- 

 nent, and thence spread to other countries. This fact of the 

 gradual increase in size of our domestic animals is all the more 

 striking as certain wild or half-wild animals, such as red-deer, 

 aurochs, park- cattle, and boars, 10 have within nearly the same 

 period decreased in size. 



The conditions favourable to selection by man are,— the 

 closest attention being paid to every character,— long-continued 

 perseverance, — facility in matching or separating animals, — and 

 especially a large number being kept, so that the inferior 

 individuals may be freely rejected or destroyed, and the better 

 ones preserved. "When many are kept there will also be a 



'Die Fflanzen der Pfahlbauten,' 



1865. 



9 Morlot, < Soc. Vaud. des Scien. Nat.' 



Mars, 1800, p. 298. 



10 Riitiineyer, ' Die Fauna der Pfahl- 

 bauten,' 1861, s. 30. 



