540 Mutations 



type in one single plant seem to be limited to the 

 admixture of the dwarf stature with the charac- 

 ters of the other new species. 



These seven novelties do not comprise the 

 whole range of the new productions of my 0. 

 lamarckiana. But they are the most interest- 

 ing ones. Others, as the 0. semilata and the 0. 

 leptocarpa are quite as constant and quite as 

 distinct, hut have no special claims for a closer 

 description. Others again were sterile, or too 

 weak to reach the adult stage and to yield seeds, 

 and no reliable description or appreciation can 

 be given on the ground of the appearance of 

 a single individual. 



Contrasted with these groups of constant 

 forms are three inconstant types which we now 

 take up. They belong to two different groups, 

 according to the cause of their inconstancy. In 

 one species which I call 0. lata, the question 

 of stability or instability must remain wholly 

 unsolved, as only pistillate flowers are produced, 

 and no seed can be fertilized save by the use of 

 the pollen of another form, and therefore by 

 hybridization. The other head comprises two 

 fertile forms, 0. scintillans and 0. elliptica, 

 which may easily be fertilized with their own 

 pollen, but which gave a progeny only partly 

 similar to the parents. 



The Oenothera lata is a very distinct form 



