558 Alterations in the Development and Forms of Plants, etc. 



unknown. Eeflecting that such mutations must be caused as a rule by 

 alteration of the sexual parts, there is every prospect of obtaining seeds from 

 the artificially altered plants. For such researches, however, Sempervivum 

 Funkii is not suitable, as it produces few ripe seeds. I used Sempervivum 

 acuminatum, another species, which can be altered in the same way as 

 Funkii. Highly altered flowers, with stamens transformed into petals, were 

 carefully self-fertilised. I thus procured a number of seedlings, which were 

 cultivated under ordinary conditions. In the fourth year of their growth the 

 seedlings came to flower. Out of 21 plants, four showed very surprising 

 deviations at the inflorescence and in their flowers. These deviations corre- 

 sponded to those artificially caused in the mother plant. With two seedlings 

 particularly, all the flowers were altered in the same manner and showed 

 transformations of stamens into petals. A third seedling had flowers, all 

 showing deviations in number and arrangement, and a fourth plant was 

 marked by the formation of small rosettes and of curious intermediate 

 forms. 



Beyond all doubt these deviating seedlings sprang from artificially altered 

 flowers, and it seems very probable that these alterations, after having 

 influenced the sexual cells, are transmitted to some descendants. The trans- 

 mission came to light after four years at the moment of flowering under 

 normal conditions of culture, and without the special methods necessary to 

 the mother-plant having been applied. 



Up to the present it is not possible to answer the most important question 

 in tlie genesis of mutations, namely, whether such alterations can be trans- 

 mitted to further generations also. These researches are not yet finished, 

 and I mention them only to emphasise the possibilities of experimental study 

 in this direction. 



Certainly it seems at present almost too much to hope that Man will be 

 successful in producing new hereditary races artificially, by experimental 

 methods. Nevertheless, the hope of controlling Nature in this respect also 

 is just what continually stimulates the naturalist and gives him strength 

 and courage to strive onward in spite of numerous disappointments and 

 failures. 



