RESULTS, PHYLETIC AND MORPHOLOGICAL 717 
the vegetative system was established and amplified, while it tended 
to become differentiated from the propagative system. Jn the later and 
more specialised heterosporous forms, and particularly in the Seed-Plants 
with their more refined methods, individual precision supersedes mere 
numbers: and reduction of the propagative system has been its usual con- 
comitant. The vegetative system which became fully distinct from the 
propagative, often retained or even increased its dimensions and complexity. 
Taking an evolutionary course of its own it diverged more and more 
in character from the propagative system. The final result is seen 
in the Angiosperms which are now, dominant: here the flowers differ 
widely from the vegetative shoots, though the plan of each resembles that 
of the primitive shoot from which both sprang. But whatever the modern 
complications may be, comparison along lines which have been pursued in 
this volume indicates that the sporophyte, which is the essential feature 
in the Flora of the Land, is referable back in its origin to post-sexual 
complications: 2¢ appears to have originated as a phase interpolated between 
the events of chromosome-doubling and chromosome-reduction in the primitive 
life-cycle of plants of aquatic habit. 
