224 



MASS MUTATIONS AND TWIN HYBRIDS OF 



table, I had another set, which contained some brunnea but no 

 lutea; it was thrown away in July. The plants on the bed flowered 

 in August. 



Table V 



O. grandifloraxO. Lamarckiana and derivatives; first generation 



0. Lamarckiana x grandiflora lorea. — Culture of 61 plants, of 

 which only one-half had been planted out on the bed and flowered 

 in August. The other half consisted in July of 22 ovata, 4 lutea, and 

 5 brunnea, giving almost exactly the same proportions as those on 

 the bed. 



0. grandiflora x 0. Lamarckiana nanella. — For this and the next 

 crosses the dwarfs of the same race were used, as for almost all my 

 previous crosses with dwarfs. I made the cross on two specimens 

 of grandiflora in 1913 and sowed the seeds of one of them in 1914 and 

 of the other in 1915. The first culture showed no contraria; the 

 second, however, was extraordinarily rich in them. It contained, 

 moreover, the lutea specimen with the flowers of a gigas. 



The group of 1914 was the first of all my cultures to show the 

 splitting. Before June only two types were distinguished, the yellow 

 plants being considered as weak specimens of the main type. About 

 the middle of June, however, they proved to have broader leaves 

 and quite different flower buds, and were considered to constitute 

 a new type. The final proof of this conception was only reached in 



