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



Immediate Effect of the Pollen Limited to the 



Endosperm. 



In view of the special mechanism operative in endosperm 

 formation, xenia has come to hold a limited meaning, a restric- 

 tion in meaning that was pointed out by one far-sighted 

 botanist at least ten years before the word came into print. 

 Certainly then, there should be no confusion in the significance 

 of the term with the morphological evidence as clear as we now 

 have it, nor is there any excuse for carrying the name of a 

 perfectly definite and limited effect over into another field 

 where the effects are from undetermined causes. But modern 

 textbooks are by no means clear on the subject, and even 

 Coulter (11) makes a statement that is so ambiguous that it 

 might entirely prevent one who did not already know from 

 finding out what xenia in corn is, instead of being able to 

 demonstrate it to his own satisfaction. The statement reads: 

 "For example, when a race of white or yellow corn is crossed 

 with pollen from a race of red corn, many of the resulting 

 kernels are red or mottled." By red corn those varieties 

 with red in the pericarp only are generally understood, since 

 corn with red pericarp is commonly enough grown as field 

 corn, and white corn crossed with pollen from this would not 

 have a red or mottled appearance. Doubtless this is one of 

 those small, ludicrous mistakes from which no first editions 

 are free; there are strains of corn with reddish endosperm, 

 no doubt, but they are not common nor would they first come 

 to mind wlien "red corn" is spoken of. If the author had 

 said blue or purple, instead of red, or colorless and colored 

 endosperm, there could have been no misinterpretation of his 

 meaning. 



In addition to ambiguity as in the above instance, the term 

 xenia suffers from many misuses that likewise render its meaning 

 obscure. What is referred to here is the abuse of the word 

 by classing as xenia influences that follow fertilization, but are 

 not brought about by the introduction of new hereditary 

 factors into that tissue in which the variation appears. In 

 none of the examples that are to be cited as having been wrong- 

 fully called xenia is there a triple fusion in which the second 

 male nucleus from the foreign pollen adds something to the 

 fusion which causes a difference in the expression. 



