268 The Pedigree Families. 



ous stems of every conceivable height between rosettes 

 which had not yet developed a stem and tall flowering 

 plants. 



In 1889 the owner of the property, having decided to 

 plant the rest of the field with trees/ had two straight 

 paths made, intersecting each other, and a semicircular 

 path to round oft that side of the field which did not 

 abut on tlie canals. On both sides of these paths the 

 ground, which is almost pure sand, was dug up to a 

 depth of three or four feet and planted with young trees. 

 Many Oenotheras were of course destroyed in this way, 

 but since that time they have spread more rapidly than 

 ever. The newly turned soil seemed to suit them; for 

 they grew on it in the most extraordinary profusion and 

 extended from it in all directions over the whole field 

 w^hose easterly half they had almost completely covered 

 bv 1894. 



It is more than natural that from such a center the 

 plant should have gradually spread in the neighborhood. 

 As early as 1888 I found it in one or two fields a good 

 way off, and since then it has occurred elsewhere ; but 

 always in relati\Tly small numbers. 



As soon as I had become acquainted (1886) w^ith 



the spot in question on the deserted potato field I saw 



that here was a wonderful opportunity of getting some 



insight into the phenomena of variation as exhibited by 



a plant which was multiplying rapidly. The diversitv 



in the form of the leaves, the height of the stem and the 



mode of branching etc. exhibited a very high degree of 



variability, and when the large bright yellow flowers 



opened in July and August I saw that almost every single 



^ In consequence of this the field is now entirely covered with 

 wood, partly consisting of oak and partly of pines, leaving hardly any 

 room for Oenotheras to grow. (Note of 1908.) 



