224 



appearance of little fruits, looked like small nuts provided 

 with three wings and strongly reminded one of the fruit- 

 lets of Eheum. It appeared that many ovules swelled, but 

 never more than one in each ovary. Not nearly in ail 

 flowers this phenomenon was observed, in no more than 

 10 to 40 percent it was at ail visible. 



For a detailed investigation thèse ovules were now fixed in 

 F 1 e m m i n g 's fixing solution (the weak solution) and then 

 washed in the usual manner and gradually placed in strong 

 alcohol. This was done for the first time on August 15 ; from 

 158 ovaries 49 ovules were obtained, i.e. 31 percent. This was 

 a maximum however, for when later material was collec- 

 ted in the same way on August 22, September 3, 10, 18, 19 

 and 25, October 8 and 22, November 12, Decembei 15 and 24 

 and on January 19, 1905, each time more and more ovules 

 appeared to be unfit for use, as they began to wrinkle. 

 Such as looked more or less swollen were fixed; among 

 thèse some had grown thicker and finally the impression 

 was that some seeds had ripened. But ultimately not a 

 single germinable seed appeared to be on the plant and 

 after January 19 no material fit for investigation could be 

 got. Nothwithstanding this, the preserved material was 

 examined, since it was possible that only the iinfavourable 

 conditions under which Dasylirion lived in the Botanical 

 TTarden at Utrecht. were the reason why no ripe seed was 

 formed. 



On microscopical examination phenomena were indeed 

 observed which seemed to point to apogamy or partheno- 

 genesis, but the material proved insufficient to obtain a 

 consistent resuit. Leaving apart even the already mentioned 

 fact that not a single ripe seed was produced, the number 

 of ovules in which ultimately anything particular could be 

 observed, was extremely small. For microscopic examination 

 revealed that most ovules which outwardly showed nothing 

 abnormal, yet were already in ail stages of disorganisation. 



