THE FLOWER 225 



{PericalUs cruenta), weakly specimens which have not com- 

 pletely developed their inflorescence in the spring, and are then 

 bedded o'ut in a shady place, will show in the course of the 

 summer some curious appearances of doubling. The connec- 

 tives of the stamens enlarge above the anthers and become 

 coloured like the 'petals, and the ray-florets develop excres- 

 cences which give them the appearance as if two ligulate 

 flowers were fixed back to back. Sometimes, too, adventitious 

 heads of flowers become developed in the axils of some of the 

 bracts of the involucre. These malformations are brought 

 about because the development of the flower takes place not 

 during the light and cool spring weather, but in shady places 

 with a considerable amount of moisture and heat during the 

 summer. 



The effect of rich manuring in transforming flowers is best 

 seen in the case of tuberous Begonias. Here it is not only 

 the male flowers which have been doubled by the transforma- 

 tions of the stamens into petals, but the female flowers too have 

 become transformed in a similar way. These flowers, too, lend 

 themselves very well for the study of such transformation. 

 The branches of the style increase in number and expand like 

 leaves. Indeed, the transformation may be more far-reaching 

 still and extend down to the ovary. In this case the ovary 

 will open, and the ovules will protrude into the flower like 

 small white grains. Indeed, when the style and the placentae 

 themselves are transformed into leaves, the ovary will have 

 seemed to have disappeared, and the ovules will cover the base 

 of the petals as a fine white powder. The ovules themselves 

 under the microscope will often show a partial transformation 

 into leaf -like organs. 



Such examples demonstrate sufficiently well the lines along 

 which the gardener has to work to secure changes in the 

 development of the various floral organs. 



