﻿438 Stout: The Origin of Dwarf Plants 



quite adequately shown in the illustrations on Plates 26 and 27. 

 The characteristics of the two types can be listed as follows: 



proportionally short 



oculiroseus. robust form-, apparently no smaller. 



While typical plants classed as robust and dwarf were very uni- 

 form in the above characteristics, there were a few plants, as noted, 

 described as intermediates or semi-dwarfs, which possessed in some 

 degree of development one or more of the characters of the dwarf 

 form but which in the second year of growth were less distin- 

 guishable. 



The mutant of Oenothera Lamarckiana that most nearly ap- 

 proaches in its characters the dwarf Hibiscus is, of course, Oe. 

 nanella. The principal characteristics of this plant compared 

 with those of the parent form as given by the description of De 

 Vries may be given as follows: 



and Secondary branches lacking or nearly 



The dwarf Oe. nanella differs from Oe. Lamarckiana in nearly 

 all of its vegetative organs. De Vries maintains, however, that 

 is brought about by a change in the activity of 



