OTHER THEORIES OF SPECIES-FORMING. 315 



selection alone. That is, noticing, somewhere, sometime, an Escholt- 

 ia individual varying slightly redder, he promptly took posses- 

 sion of it, raised young poppies from its seeds, selected from among 

 them those varying in a similar direction, raised new generations 

 from them and so on until now he who wishes may have his 

 California poppies of a strange glowing crimson for the price of a 

 little package of seed, where formerly he was perforce content 

 with the golden orange. For me the golden orange suffices, but 

 that does not detract from my eager interest in the flower-painting 

 methods of Mr. Burbank. Even more striking a result is his blue 

 Shirley poppy, produced also solely by repeated selection from 

 the crimson field poppy of Europe. 'We have long had various 

 shades of black and crimson and white poppies, but no shade of 

 blue. Out of 200,000 seedlings I found one showing a faintest trace 

 of sky blue and planted the seed from it, and got next year one 

 pretty blue one out of many thousand, and now I have one almost 

 pure blue.' 



"But another brilliant new poppy was made in a different way. 

 The pollen of Papaver pilosum, a butter-coloured poppy, was put 

 on the pistils of the Bride, a common pure white variety of 

 Papaver somniferum (double), and in the progeny of this cross was 

 got a fire-coloured single form. The character of singleness was 

 common to the ancestors of both parents, the character of fire colour 

 in the lineage of somniferum only, although the red of the new 

 iorm is brighter than ever before known in the somnifera series. 

 Both characteristics were absent (or rather latent) in both parents. 

 And yet the perturbing influence of the hybridisation brought to 

 the fore again these ancestral characters. The foliage of this fire 

 poppy is intermediate in type between that of the two parents. 



"The history of the stoneless and seedless plum, now being 

 slowly developed by Burbanks, shows an interesting combination of 

 selection, hybridisation, and reselecting. Mr. Burbank found a 

 plum in a small wild plum species with only a part of a stone. 

 He crossed this wild species with the French prune; in the first 

 generation he got most individuals with whole stones, some with 

 parts of a stone, and even some with no stone. Through three 

 generations he has now carried his line by steadily selecting, and 

 the percentage of no-stone fruits is slowly increasing, while quality, 

 beauty, and productiveness are also increasing at the same time. 



"The plum-cot is the result of crossing the Japanese plum and the 

 apricot. The plum-cot, however, has not yet become a fixed variety 

 and may never be, as it tends to revert to the plum and apricot 

 about equally, although with also a tendency to remain fixed, which 

 tendency may be made permanent. 



