Variegated Leaves. 275 



different from that of the typical form, Init as soon as 

 reversion occurs through bufl-variation all these second- 

 ary characters are dispersed at once, the green leaves be- 

 coming dattened out, assuming the normal form, and 

 often attaining twice the size of the variegated ones. In 

 this way the reverted branch easily strikes the eye. I ob- 

 served this most beautifully in Casfanea vesca and Uliiius 

 caiiipestris, but Kerria japojiica and many other species 

 show it as well. 



The question which btids are most likely to give rise 

 to atavistic branches has been much discussed, and the 

 general opinion seems to be that the rhizome and the 

 adventitious buds on the roots are most prone to rever- 

 sion. Thus Glechoina hederaceinn variegatum often pro- 

 duces green rtmners^ whereas the variegated Tussilago 

 Farfara breeds true from its runners. For the last ten 

 years I have had a variegated plant of Riibiis fniticosns 

 which has produced both green and variegated plants 

 from its radical buds In proportions which vary according 

 to conditions, and to the year. It seems to me probable 

 that the weaker buds are most likely to give rise to ata- 

 vists : but since this results in the production of green 

 branches which grow much more vigorotisly than the 

 neighboring variegated ones, it is not easy to decide this 

 point.- 



Variegated branches on green plants are almost as 

 common. It is the general idea amongst gardeners that 

 the numerous variegated varieties of woody plants have, 

 wn'th few exceptions, arisen in this way. One of these 



^Verlot, he. cit., p. 78. 



' Tn papers on this subject we often come across an expression 

 of the opinion that it is the strongest branches which become green ; 

 but this view, no doubt, is largely due to a misapprehension of the 

 relation between the cause and its effect, as explained in the text. 



