CHAPTER XVII. 
True Nature of Floral Organs; Details of their 
Structure. 
187. The Flower a Shortened and Greatly Modified Branch. 
Fic. 136. — Transitions from Petals to Sta- 
mens in White Water-Lily. 
E, F, G, H, various steps between petal 
and stamen. 
bracts end and the sepals begin. 
—TIn Chapter IX, the leaf- 
bud was explained as being 
an undeveloped branch, 
which in its growth would 
develop into a real branch 
(or a prolongation of the 
main stem). Now since 
flower-buds appear regu- 
larly either in the axils of 
leaves or as terminal buds, 
there is reason to regard 
them as of similar nature 
to leaf-buds. This would 
imply that the receptacle 
corresponds to the axis of 
the bud shown in Fig. 60, 
and that the parts of the 
flower correspond to 
leaves. There is plenty of 
evidence that this is really 
true. Sepals frequently 
look very much like leaves, 
and in many cactuses the 
bracts about the flower are 
so sepal-like that it is im- 
possible to tell where the 
The same thing is true of 
