lo BREEDING 



elsewhere in the vegetable kingdom, and these two 

 forms are regarded as true species ; whilst the cha- 

 racter of 0. nanella, which is regarded as a variety, 

 not only occurs in the pea and in other plants, but 

 also amongst the new forms which have arisen from 

 0. Lamarckiana. In fact the single exception referred 

 to amongst the 450 plants raised from the first 0. 

 gigas was a plant which had all the characters of 

 0. gigas, but possessed the dwarf habit of 0. nanella, 

 and should be designated 0. gigas -nanella. 



Professor de Vries has drawn this further ex- 

 tremely important distinction between specific and 

 varietal characters. Specific characters, according 

 to him, blend in inheritance; whilst varietal ones 

 behave in Mendelian fashion when crossed. Indeed, 

 he makes the behaviour of a particular character 

 when crossed the test whether it is a varietal or a 

 specific one. Professor de Vries has made a number 

 of crosses between 0. gigas and other species of 

 (Enothera, For instance, 0. gigas, crossed with 0. 

 Lamarchiana, gives rise to forms which are a blend 

 between their two parents, and moreover breed true 

 to this intermediate character. The conclusion to 

 which he comes in the paper in which he describes 

 these results is stated as follows by him : "In all 

 these respects, and in others as well, 0. gigas 

 behaves as a true species when crossed, and not as 

 a variety, as 0. nanella does when crossed with the 

 same forms." There are certain complications in 

 the case of 0. nanella, but these need not detain us 

 now. Full details can be found in the paper referred 



