64 MUTATIONS, VARIATIONS, AND RELATIONSHIPS OF THE OENOTHERAS. 



mcnt proceed that one of the atypic individuals opened a flower-bud on No- 

 vember 27, 1905, and seeds were harvested before the beginning of the year. 

 Other lots of seeds were obtained throughout the year and several sowings 

 were made, with the result that the atypic form was found to transmit its con- 

 stellation of characters to its offspring. Among the full}^ atypic individuals, 

 of which a few hundred have been grown, one was found with wide leaves like 

 the parental form, another with ciliate leaves, and another with undulate 

 leaves. This activation of parental characters is one fully illustrated by 

 lamarckiana and its derivatives and shows that the treatment has simply 

 thrown certain parental characters into a state of latency and awakened 

 others with which the parental characters are mutually exclusive as to external 

 manifestation. These individuals did not afford a transition or intergrading 

 series between the derivative and the parental form, however (plate 10). 



In the summer of 1906 a second series of injections was made, with the result 

 that capsules treated with zinc sulphate, i part to 2000 parts of distilled 

 water, yielded seeds which produced progeny inclusive of the atypic form 

 described above, and also some other combinations which it has not been 

 possible to follow in successive generations. The group, however, bears a 

 general resemblance in relationship to that of the lamarckiana mutants. 



An injection wdth calcium nitrate, i part to 1000 of distilled water, was 

 without effect and the progeny were all of the parental type. It was remark- 

 able, however, that a treatment with this substance in the previous season 

 had secured some atypic forms, probably due to some opportune condition in 

 the experiment not yet understood. Furthermore, the plants of the progeny 

 of the first treatment which were apparently normal yielded seeds which gave 

 a few atypic forms, indicating that the effect of the first treatment had been 

 more or less permanent. Confirmation of this important matter has not yet 

 been obtained, however. Then, again, an injection of ovaries in 1906 with the 

 distilled water subject to impurity from the still and from the syringe, as men- 

 tioned above, also resulted in a progeny in which some atypic forms were 

 found to occur. So far, then, as experience with this plant is afforded it is to 

 be seen that a variety of agents act in inducing discontinuous variation in the 

 progeny and that in one instance the variability was carried to the third 

 generation, as far as that part of the test has been extended. The atypic 

 forms transmit their qualities perfectly from generation to generation, and 

 the third generation now in hand are like the first from which they came 

 originally. 



