THE ANDROECIUM 



101 



displacement (the displacement tlieory). Under the intercalation 

 theory, a new whorl of stamens was considered interposed between 

 the corolla and the lower stamen whorl. Under the dedouhlement 

 theory, the alternate new members were formed by "dedouhlement," a 



Fig. 47. Floral diagrams of polystemonous androecia showing reduction in the 

 androecium; transformation of lateral members of the stamen fascicles into nec- 

 taries and reduction in number of the whorls. A, Umbelluhria calijornicu: the inner 

 whorl vestigial, the next outer whorl of nectary-bearing fascicles, the two outer 

 whorls of simple stamens. B, C, Laurus nobilis: staminate Hower B with two whorls 

 of nectary-bearing fascicles and one whorl of stamens; pistillate flower C with one 

 whorl of staminodes. ( After Kasapligil. ) 



Fig. 48. Floral diagrams showing paired stamens ( dedouhlement) in the outer 

 whorl of androecium. A, Sagittaria sagittifolia; B, Butomus umbellatus. {After 

 Salisbury.) 



doubling by radial splitting of the original outer whorl (Fig. 48). 

 Under the Carpel Polymorphism theory, it has been claimed that 

 obdiplostemony transgresses the law of alternation of successive whorls, 

 but, in androecia with more than two whorls of stamens, there is com- 



