Oenothera Riihrincrvis. Z27 



0. gigas has appeared twice again, but not directly 

 from O. Lamar ckiana. It appeared once in 1898 from 

 the seeds of a plant of O. sublinearis which had itself 

 arisen from the Lamarckiana-iam'ily. It appeared again 

 in 1899 from a cross made between 0. lata and O. Jiir- 

 tella, a new species which did not arise from my mutating 

 families but turned up among the seeds which I had 

 bought. 



I succeeded in getting the first of these ^z^a^-plants 

 to flower, but it was annual and did not flower till the 

 beginning of October, too late for the seed to ripen. 

 I therefore compared the plant very carefully with the 

 other plants of that species which I had growing at that 

 time, and which were raised from gigas-SQeds; it agreed 

 with them in all essentials. 



The plant which mutated from 0. lata died as a 

 rosette and never developed a stem. 



§ 13. OENOTHERA RUBRINERVIS. 



This form unlike Oenothera gigas, is one of the com- 

 monest of my new species. It has arisen, altogether, 

 66 times from O. Lamarckiana or from other families 

 or cultures. It is hardly necessary to state that among 

 the ancestors of these mutants, as far as I have had them 

 under observation, there have been no examples of riibri- 

 nervis. And, as the genealogical tables given above 

 show, most of the mutations arose in families which had 

 been under observation for many generations. 



The 66 mutated plants belonged to a single type. 

 They did not differ more from each other than the 

 members of a culture raised from the seeds of a single 

 one of them. Each of the characters, which have al- 



