96 Selection Does Not Lead to Origin of Species. 



often grown in our neighborhood and can be distin- 

 guished from our common form only by its somewhat 

 more ''branching habit." 



I can find nothing — not even a suggestion — in Metz- 

 ger's account about the cause of this transformation. 

 But any one having an acquaintance with hybridization 

 and the so-called running out of cereals will see that Metz- 

 GER^s case is not an instance of the transformation of a 

 race by climatic influences. The cultures of the Taras- 

 cora maize stood between other kinds and were obviously 

 liable to be fertilized by the pollen of these through the 

 agency of the wind. Some of the seeds would in that 

 case give hybrids which could give rise in the third gen- 

 eration to pure European maize. -^ 



The hybrids and their pure European progeny would 

 be likely to supplant the foreign strain which would be 

 less adapted to the climate of Baden; and this would take 

 place in a much shorter time than one would be inclined 

 to think. And inasmuch as this supplanting of one sort 

 by another has been so often mistaken for the supposed 

 transformation of a species or even for the creation of 

 a new one it is worth while to cite in some detail a few 

 examples which may be selected from Rimpau's cele- 

 brated w^ork : Rislers Wcizenhaii. The first example is 

 an observation of Risler;- the second is due to Rim- 

 PAU himself. 



RiSLER describes a case of degeneration of GaUand 

 wheat during the first few years after its introduction 

 into his estate at Caleves on Lake Geneva in Switzer- 

 land. The ears of this variety, when they make their 



^A more exact discussion of this point will be given elsewhere. 



^EuG. RiSLER, Der Weisenbau. Translated by W. Rimpau; 

 Thaer-Bibhothek, P. Parey, 1888, pp. 73-74. 



i 



