2 



males show no development of the female or- 

 gans. 



Professor Doncaster, of the University of 

 Cambridge, England, has tested the influence 

 of Ustilago violacea upon Lychnis dioica by 

 artificial infections, and his results completely 

 corroborate the conclusions of Strasburger. 

 He sends for publication in SCIENCE the fol- 

 lowing brief account of his experiments: 



It is well known that Lychnis vespertina is 

 dioecious, but that all plants infected with the 

 fungus Ustilago have well-developed stamens. 

 Some of these plants have the typical male form, 

 without trace of ovary; others have a vestigial 

 ovary and styles in addition to the stamens and 

 anthers filled with Ustilago spores. This suggests 

 that when a female plant is affected by the para- 

 site, the stamens are caused to develop and the 

 ovary is reduced, while the form of the flower of a 

 male which is infected is not altered. In order to 

 test this suggestion, I planted some ustilaginized 

 plants in my garden in the late summer of 1910, 

 and put with them some uninfected plants which 

 I attempted to infect by sprinkling them with 

 spores and by rubbing spores into parts of the 

 stem from which I had scraped away the epi- 

 dermis. The results were as follows: Of seven 

 females which I attempted to inoculate in August, 

 1910, one became infected, and had the typical 

 "hermaphrodite" form of flower in October, but 

 in June, 1911, was again quite free from Ustilago, 

 and had typical female flowers. A second female 

 plant showed infection in June, 1911, but only on 

 part of the plant; one branch was quite clean and 

 had typical female flowers, the rest of the plant 

 was infected and had "hermaphrodite" flowers. 



Of eight male plants which were inoculated in 

 August, three showed some infected flowers before 

 the end of September; the anthers contained 

 Ustilago spores, but there was no change from 

 the male type of flower. Three of these eight 

 plants were dead in June, 1911; one of the re- 

 maining five was infected. 



Of five ustilaginized plants transferred to the 

 garden, four had the hermaphrodite type of flower 

 and one the male. One of the hermaphrodites so 



