128 Selection Does Not Lead to Origin of Species. 



prominent breeders in the Netherlands, has written an 

 account of this practice as followed in his country. There 

 are certain districts in which particular kinds of cereals 

 retain their valuable characters unimpaired and from 

 these other less fortunate districts obtain their seed. For 

 example the Zeeland wheat only retains its beautiful 

 white color in Zeeland; in Groningen and Friesland this 

 character is lost in a few generations. Flax seeds are 

 obtained from Riga and only quite exceptionally can 

 they be grown witliout renewal for more than three 

 or four years ; for degeneration soon sets in, especially 

 in respect of resistance to disease. A whole list of fur- 

 ther examples leads us to the conclusion that repeated 

 purchase of new seed stock from better localities is ab- 

 solutely indispensable in the less favored districts. 



The so-called process of ''Intermediate Generations" 

 is adopted in the case of the sugar beet especially. One 

 or at most two generations are interpolated between the 

 liarvest of the seeds of polarized beets and the seed for 

 sale. The object is to cover the cost — which is very 

 high — of the polarization process and of selection, by 

 vastly increasing the amount of seed for sale. 



The more drastically selection is carried out the 

 smaller does the number of select beets become and, con- 

 sequently, also the amount of seed that can be obtained 

 from them. It is necessary therefore to increase the 

 quantity of seed, and, moreover, to do this in short time 

 in order to reduce the amount of degeneration, due to 

 the interpolation of many generations, to a minimum. 

 A very curious method is adopted to effect this. The 

 seed plants are not sown the usual distance apart but so 

 close that the beets are only as thick as one's finger. The 

 result of this is that the stem is only slightly branched 



