No. 511] NOTES AND LITERATURE 



441 



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distributed to the daughter cells more or less according to chance. 

 If a cell receives only white chromatophores this cell will have 

 only white descendants. If a cell receives only green chroniato- 

 phores its descendants will be pure green cells. A cell receiving 

 both kinds may later produce either pure white or pure green at 

 any cell division. Should a cell which is later to develop into 

 cotyledons and growing point receive only one kind of chro- 

 niatophores, then the resulting seedling will appear to be only 

 pure white or pure green, as the case may be. Since pure white 

 cells may have only pure white descendants and pure green only 

 pure green, while mixed cells may have three kinds of descend- 

 ants, it naturally follows that after many cell divisions the per- 

 centage of mixed cells in the plant practically vanishes. 



The above hypothesis makes only one assumption that is not 

 demonstrated ; that is, that the fertilized egg cell has two kinds 

 of chromatophores, namely : white and green. According to cur- 

 rent teaching the chromatophores are derived entirely from the 

 egg cell ; but, according to the author, this may well be considered 

 not an established fact. If current teaching on this point is cor- 

 rect, then we have here a very remarkable case. It would then 

 be necessary, according to Dr. Baur, to assume that in the cross, 

 female white on male green, a part of the white chromatophores 

 of the egg may become green under the influence of the male 

 nucleus, and that iii the reciprocal cross a part of the whit 



matophores would have to 

 the male nucleus. Such a 



sexual cell carries chromat 

 albomarginate character is 

 These results of Dr. Bai 

 chromatophores from one 

 writer would suggest anot 

 nomena discussed above, 

 into the cell something wh 

 but is cytoplasmic in its na 

 to a part of the cytoplasm ( 

 in the chemical constitute 



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