The Mutations in the Larnarckiana-Fainih. 243 



The fruits are short and thick and contain relatively 

 few but, as a rule, large seeds. 



O. lata appeared pretty regularly in my cultures, but 

 in proportions which varied greatly. And as they could 

 be easily and certainly recognized, even under unfavor- 

 able circumstances such as crowding, these deviations 

 are indices of a real variability in proportions and not 

 of the difficulty of identification which may have affected 

 the proportions in the case of the other forms. The pro- 

 portion of lata plants was sometimes as low as 0.1% ; in 

 the fifth generation it was as high as 1.8% ; i. e., about 

 the same as that of O. oblong a. 



VII. O. scintillans. Except for 0. gigas which has 

 so far only arisen three times, and 0. spathulata, 0. subo- 

 vata, O. leptocarpa and others which I shall refer to later 

 on, O. scintillans is by far the rarest form in my cultures. 

 It arose only eight times in the Lamarckiana-idimWy , and 

 in other families still more seldom. 



It does not, like the other species, breed true when 

 self-fertilized, but behaves in a very peculiar way. Seeds 

 from it give rise to three forms in considerable numbers : 

 0. scintillans, O. oblonga (Fig. 44 on page 233) and 0. 

 Lamarckiana. 



This is a different phenomenon from that with which 

 we are already familiar in the other elementary species, 

 namely the ver}^ occasional production of a mutation in 

 about 1 in 1000 plants. There often arise in this way 

 elementary species of the second order, i. e., species which 

 combine the characters of two species. These also arise 

 in the case of 0. scintillans; e. g., 0. scintillans nanclla 

 and 0. scintillans elliptica. But only very occasionally, 

 i. e., one such among thousands of normal O. scintillans. 



A verv remarkable feature of this instabilitv of O. 



