82 
tion and nature of the germ plasm which seis new characters 
tative and quantitative nature, in one or more of the assumed 
units which are individually only indirectly concerned with the 
ct 
c er. 
urthermore, . sults of extensive experimental selections 
indicate clearly that a panies variations in a species or even 
in a race are Bae which present numerous 
gradations Bek 2 imme: The distinction between dis- 
continuous variation or mutation, and variation that is decided] 
indiscriminate and continuous in quite the Darwinian sense, is 
wth compose: 
great numbers of perennial plants, with the resulting interbreed- 
ing that ensues especially between forms that may arise by 
spontaneous variation 
