THE PLANT WORLD. 155 



son, perhaps 40 or 50, and nearly all were fertile but rapidly passing 

 with decay. 



They corresponded more in number, size and condition to the 

 second year's appearance three seasons ago, as their decay is (piite 

 rapid when once it has commenced it is fair to presume that the number 

 of individuals this year was double or treble, perhaps reaching 100 or 

 150, early in the season. No molestation has occurred to the clump, 

 conditions remaining the same as last year. 



It has now been shown that every third season is one of either great 

 profusion or nearly absence and the intervening year of intermediate 

 quantities. The real proof however must be shown next season. 



I had no opportunities to study <). vulgatumj beds. 



I would like to hear the results of those able to work out these 

 underground intricacies. 



Xenia, or the immediate effects of Pollen on Maize. This is the 

 title of Bulletin No. 22, Division of Vegetable Physiology and Patho- 

 logy, by Herl)ert J. Webber, in charge of the Plant Breeding Labora- 

 tory of that Division. The paper is technical, but the subject discussed 

 has a broad practical application in the work on plant breeding now 

 under way. 



Xenia is the supposed immediate or direct effect of pollen on the 

 character of seed and fruits, and is a phenomenon which for years has 

 puzzled botanists and plant breeders. Until recently no satisfactory 

 theory has been advanced to explain how the influence of hybridization 

 could pass outside of the fecundated embryo and cause changes in other 

 portions of the seed or fruit. However, in a recent article, DeVries 

 calls attention to the discovery of double fecundation as probably fur- 

 nishing an explanation of the phenomenon of xenia. Almost simulta- 

 neously with appearance of DeVries' s paper Currens published a sum- 

 mary of his studies on xenia on maize in which the same conclusion is 

 reached. 



A number of experiments were conducted by Mr. Webber, with 

 a view of obtainins: evidence of the bearing: of dou))le fecundation on 

 the problems of hybridization and the results of this examination are 

 ofiven in the bulletin. It is illustrated with 4: plates. 



