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



parts of the seeds. In these plants xenia would not become 

 patent until the seeds were cut open and the endosperm tissue 

 disclosed. 



In members of the Graminaceas, and especially in the culti- 

 vated cereal crops with their superior development of endosperm, 

 xenia has been observed for a long time. Until recently it 

 has been marveled at, not only by agriculturists, who probably 

 first saw the phenomenon, but also by botanists, who noted, 

 yet were unable to account for it. Many of the latter were 

 unwilling to credit the possibility of an immediate effect of 

 pollen and they attempted to explain what they saw as the 

 result of previous hybridization. 



Origin of the Name. 



The word xenia, (Gr. xenios), means hospitality. When in 

 1881, FoCKE (2) first named the influence of foreign pollen, he 

 evidently had in mind only the genial, (or xenial), relations 

 existing between guest and host and in his own words, regarded 

 this variation from the normal form as a present from the p)lant 

 given pollen to the one taking it (Gastesbeschenk). He did 

 not limit the extent of the influence to any special tissue or 

 part of the plant, so we find him passing without an effort from 

 xenia in maize, an actual case, to an effect in peas in which 

 the seed coat and even the pod color is involved. He likewise 

 applies the name xenia to a darkening observed in grapes, 

 when pollen from a dark variety was transferred to a variety 

 of lighter color. Presumably, in this case it is the pericarp 

 that is to be understood. If the pericarp is meant the example 

 cannot be properly classed as xenia, as will be shown later. 

 In peas, vetches and lilies mentioned in his writings as illus- 

 trations of xenia the variations are more than likely due to a 

 previous cross fertilization and hybridity rather than to any 

 immediate effect of the pollen, and Focke himself so additted 

 by taking the precaution to state that he was not sure that 

 these citations were after all, xenia. 



It is worth while noting that previous hybridity had always 

 been the stumbling block in the paths of those whose efforts 

 were directed towards demonstrating the existence of xenia, 

 and it was to disprove allegations of hybridity, I mean hybridity 

 resulting from a cross fertilization taking place at some unknown 

 time in the past, that a number of the early experiments were 



