276 The Ohio Journal of Science [Vol. XVII, No. 8, 



since double fertilization properly describes eggs fertilized by 

 two sperms. In triple fusion the fusion has nothing to do 

 with the fusion of the egg and the sperm, but bodies outside 

 the egg fuse with another sperm. Shortly after Nawaschin's 

 paper was read, Guignard (7) published a complete description 

 of triple fusion with a number of figures announcing that the 

 process is common throughout the angiosperms generally 

 instead of being limited to the Liliacese, as was first supposed. 

 The year before this significant morphological evidence was 

 made known, Correns in the paper above referred to, drew the 

 inference that triple fusion possibly was the means of explaining 

 xenia, though no detailed researches on the development 

 of the endosperm had been undertaken. The relation between 

 triple fusion and endosperm formation also was suggested. 

 It remained for Guignard (8) in 1901 to clear up all doubt as to 

 the occurrence of the same process in maize as takes place in the 

 formation of endosperms of other angiosperms. In a number of 

 different species Merrel, Land, Coulter and others have 

 demonstrated that triple fusion is general among the angio- 

 sperms, the typical case being where two polars, one micropylar 

 and the other antipodal, of the female gametophyte, fuse to 

 form the definitive nucleus. It is with this nucleus that the 

 second male cell from the pollen tube unites. 



As soon as it became certain that there is a triple fusion 

 in the formation of the endosperm, xenia was no longer a mystery 

 but is now regarded as an occurrence as normal as seed formation 

 itself. The writer (9) pointed out somewhere else that it is a 

 simple matter to demonstrate xenia experimentally in definite 

 areas on an ear of corn as desired, and was able to produce an 

 ear, a photograph of which appears in the paper referred to, on 

 which about one-fourth of the grains appeared blue, while the 

 grains in near by rows were pure white. This was done by 

 careful manipulation of the silks and the application of pollen 

 from a race of contrasting color in the aleurone layer. The 

 value of this experiment is twofold, for it establishes the 

 fact that the variation is due to an effect of the pollen, since only 

 those grains within that area in which it was desired to produce 

 the color appeared blue, and second, because the occurrence was 

 in harmony with the expectation it was explainable as the 

 normal result of the chromosome mechanism. What is this 

 mechanism that causes xenia? In the processes preceding 



