274 



SUMMARY. 



Metamorphosis : the "Flower" has been evolved 

 from an elongated leafy shoot, with the "cone " as an 

 intermediate stage ; an analogous example of the pro- 

 cess is seen in the Pteridosperm — Bemiettites — Cycad 

 phylum. The changes concerned, as they affect the 

 four floral whorls and the sporophylls of Cryptogams, 

 are Phyllody, Squamody, Bracteody, Sepalody, Peta- 

 lody, Zygomorphy, Pelory, Staminody, Carpellody, 

 and Sporangiody. Among the subjects discussed are 

 the morphology of the " corona " in Amaryllidaceae, 

 and that of anther-structure. Many phenomena under 

 this heading are reversionary, while others are pro- 

 gressive. 



Under the heading of Simplification are included : 

 (1) Abbreviation of the inflorescence and flower; this 

 is the opposite condition to proliferation ; (2) adnation 

 of floral axes, either with each other, or with floral 

 leaves ; or the adnation of floral leaves ; (3) cohesion, 

 including synanthy or the union of entire flowers ; and 

 negative dedoublement, in which the tendency towards 

 fusion overrides that towards division ; (4) suppression^ 

 representing the final stage in the reduction-process, 

 in which floral members or whorls become completely 

 eliminated. Negative dedoublement and suppression 

 are considered with reference to the various floral 

 whorls. 



Simplification of the flower by means of cohesion 

 and suppression of its members represents one of the 

 main processes of floral evolution. The tendency to- 

 wards division and multiplication, as shown here and 

 there in the ontogeny of floral members, is a rever- 

 sionary phenomenon. 



Adventitious flowers and fruits are finally described,, 

 and special attention is drawn to the occurrence of 

 endogenous flowers in Salix. 



