THE AMERICAN BOTANIST 145 



Geitonogamy and Xenogamy. — Usually we distinguish 

 two general methods of pollination in flowers which we differ- 

 entiate as self or close pollination and cross pollination. There 

 is, however, some uncertainty as to exactly what these terms 

 mean. Take self pollination, for instance. Is this merely a 

 transfer of pollen from the stamens to the stigmas, in the same 

 flower, or does this term cover the transfer of pollen from 

 flower to flower on the same plant? Species are multiplied 

 in two ways, vegetatively and by seeds. Individuals that are 

 produced vegetatively are essentially parts of a single plant. 

 Is the transfer of pollen from one concord grape vine to an- 

 other or one Jonathan apple to another self pollination? 

 These plants are multiplied vegetatively. Orchid pollen may 

 be carried half way around the earth and still be effective. Is 

 pollination of this kind self pollination? Such complications 

 have been recognized in part by botanists and several terms 

 have been formed for more definitely indicating different 

 phases. Thus autogamy is what would ordinarily be called 

 self or close pollination — the transfer of pollen from stamen 

 to stigma in the same flower. Geitonogamy is the term used 

 to describe the transfer of pollen between different flowers on 

 the same plant, but a distinction is rarely made between this 

 phase and the transfer of pollen between plants of the same 

 species, whether such species are derived from some original 

 species by cuttings or seeds. Plants from seeds, however, may 

 be quite different from plants made from cuttings, since in one 

 case the seeds may have been produced by cross-pollinated flow- 

 ers and thus have united in their structures two lines of des- 

 cent. Some students would call any transfer of pollen between 

 two plants cross pollination or Xenogamy, but if this term 

 denotes a cross between two plants of the same species, what 

 shall we call a cross between two different varieties, not to 

 mention crosses between two different species or, in rare cases,, 

 between species of two different genera? Botanists are not 



