V] MODIFIED ORGANS 45 



evidence obtained by comparing the spore-bearing organs 

 of a very large number of plants, both with and without 

 flowers, and, still more, the development of the parts 

 referred to, which are found to arise on the axis just as 

 do leaves, and in fact to be indistinguishable from leaves 

 in their earliest stages in position, mode of growth, and 

 internal structure. These matters can only become clear 

 after more knowledge, but it seems advisable to give this 

 preliminary sketch of the grounds for asserting that the 

 flower is essentially a shoot, or branch, the parts of which 

 have become modified for special purposes connected with 

 reproductive processes ; and that these modified parts are, 

 as regards origin and mode of development, the same 

 things as leaves. 



The beginner must also be on his guard against false 

 assumptions regarding the words " modified " or " meta- 

 morphosed " as used in the preceding sketch. The state- 

 ment that a stamen is a modified or metamorphosed leaf, 

 is in the same category as the statement that a tendril is 

 a modified leaf, or branch, as the case may be ; and means, 

 not that the individual organ in any given phase in the 

 history of the individual plant was ever actually a leaf, 

 and then changed ; but that according to the relations of 

 position, order of development, and fundamental structure, 

 it is produced as the representative of a leaf, and that far 

 back in the distant past, the forces then at work on such 

 shoots would have induced the development of unmis- 

 takable leaves where we now find these organs. Indeed 

 such a reversion to the ancestral type is by no means 

 uncommon to-day, and every gardener knows how promising 

 flower-buds may " change their minds " as it were and 

 become foliage shoots after all. 



Sufficient has now been said to justify the treatment 

 of the flower, and its parts, as portions of the shoot- 



