PERFECT FLOWERS 79 



While these visits are proceeding the style is 

 growing out and the stigma is expanding, so that in 

 the lower flowers we find it fully developed and 

 open with three points turned back. The pollen has 

 all disappeared and the stamens are curled up and 

 withered. So that this blossom, which can have 

 none of its own pollen, is ready to receive and hold 

 fast any that is brought to it by a bee who swoops 

 down to it from the upper blossoms of the bell- 

 flower which he last visited. 



The Venus's looking-glass, Canterbury-bell, and 

 Platycodon exhibit the same course of development. 

 The contrivance of stamens and pistils is in reality 

 a simple mechanism for bringing about cross-ferti- 

 lisation, the first of the sort we have seen, but hence- 

 forward we may search for such mechanisms, of 

 which there are many. 



MINT FAMILY 



All the members of the Mint family which I have 

 so far been able to investigate, with the exception 

 of the horse-balm, seem to have the common habit 

 of developing and shedding pollen before the pistil 

 ripens. 



The Scutellaria, as in the sketch, and self- 

 heal (Prunella vulgaris) have this peculiarity in 



