348 MORPHOLOGY OF STAMENS. [BOOK i. 



organ from the structure of the leaf, by a modification of 

 which it is produced ; and, at first sight, in many cases, it 

 appears impossible to discover any analogy between the type 

 and its modification; as, for instance, between the stamen 

 and leaf of a Rose. Nevertheless, if we watch the transitions 

 which take place between the several organs in certain species, 

 what was before mysterious, or even inscrutable, becomes clear 

 and intelligible. In Nymphsea alba the petals so gradually 

 change into stamens, that the process may be distinctly seen 

 to depend upon a contraction of the lower half of a petal into 

 the filament, and by a development of yellow matter within 

 the substance of the upper end of the same petal on each 

 side into pollen. A similar kind of passage from petals to 

 stamens may be found in Calycanthus, Illicium, and many 

 other plants. Now, as no one can doubt that a petal is a 

 modified leaf, it will necessarily follow, from what has been 

 stated, that a stamen is one also. But it is not from parts 

 in their normal state that the best ideas of the real nature 

 of the stamen may be formed ; it is rather by parts in a 

 monstrous state, when reverting to the form of that organ 

 from which they were transformed, that we can most cor- 

 rectly judge of the exact nature of the modification. Take 

 for example that well-known double Rose, called by the French 

 R. QEillet. In that very remarkable variety, the claw of the 

 petals may at all times be found in every degree of gradation 

 from its common state to that of a filament, and the limb 

 sometimes almost of its usual degree of development, some- 

 times contracting into a lobe of the anther on one side, or 

 perhaps on both sides, now having the part that assumes 

 the character of the anther merely yellow, now polliniferous, 

 and finally acquiring, in many instances, all the characters 

 of an undoubted though somewhat distorted stamen. Double 

 Pseonies, Double Tulips, and many other monstrous flowers, 

 particularly of an icosandrous or polyandrous structure, afford 

 equally instructive specimens. It is for these reasons that it 

 was stated in the Outlines of the first Principles of Botany, 

 p. 307., that "the anther is a modification of the lamina, 

 and the filament of the petiole." 



I ought, perhaps, to have put the explanation in a more 



