796 Fluctuations 



yields higher percentage-figures in a dry region 

 than in a wet one. This is seen when compar- 

 ing, for instance, the results of the analyses 

 from the sandy provinces of Holland with those , 

 from the clay-meadows, and it is very well 

 known that Californian beets average as high 

 as 26^ or more, while the best European beets 

 remain at about 20^. As far as I have been 

 able to ascertain, these figures however, are not 

 indicative of any difference of race, but simply 

 direct responses to the conditions of climate 

 and of soil. 



Apart from these considerations the improve- 

 ment reached in half a century or in about 

 twenty to thirty generations is not suggestive 

 of anything absolute. Everything is fluctuating 

 now, even as it was at the outset, and equally 

 dependent on continual care. Vilmorin has 

 given some figures for the beets of the first 

 generations from which he started his race. He 

 quotes 14^ as a recommendable amount, and 7 

 and 21 as the extreme instances of his analy- 

 ses. However incorrect these figures may be, 

 they coincide to a striking degree with the pres- 

 ent condition of the best European races. Of 

 course minor values are excluded each year by 

 the selection, and in consequence the average 

 value has increased. For the year 1874 we find 

 a standard of 10 - 14^ considered as normal. 



