20 PLANT-BREEDING 



the latter often becoming ovate instead of cordate. The 

 other had very short styles, the stigma reaching only to the 

 mouth of the flower-tube, instead of being Ufted up above 

 the anthers. Its ovary is only partly inferior, and it ripens 

 only very few seeds in its capsules, which remain small. It 

 has, moreover, some associated characters in its fohage by 

 which it may be recognized before the flowering-period. In 

 my cultures, both these varieties were found to be constant 

 and pure from seed. Some further mutations have been 

 produced on the same field, but since they were also produced 

 in my experiment-garden, I shall not here mention them 

 separately. 



In the year 1886, I collected some seed from the normal 

 plants of this field and sowed them in my garden the next 

 spring. This culture at once gave a new mutation wholly 

 unobserved until that time. Three individuals diverged 

 from the average, and all three in the same way. They con- 

 stituted a new type which has been called QEnothera lata or 

 the broad-leaved evening primrose. Its leaves have rounded 

 tips, its stems are weak and bending and scarcely reach half 

 the size of those of Lamarck's primrose. It has thick flower- 

 buds and produces flowers the petals of which often cannot 

 completely flatten themselves. The anthers are barren of 

 pollen, dry and twisted. Its ovary, however, is normal and 

 can easily be fertiKzcd by the pollen of the parent species. 

 In doing so the next generation is, of course, of hybrid origin, 

 but it does not produce intermediates but consists of some 

 typical CEnothera lata and some normal CEnothera Lamarck- 

 iana. By repeating the cross the lata type maybe kept indefi- 

 nitely, occurring in about the same numerical proportion 

 in each generation. 



Starting from these mutations, I began a regular scientific 

 pedigree culture of Lamarck's evening primrose, fertilizing 

 the flowers artificially v/ith their own pollen, protecting them 



