THE STONECROPS 



It is in the flowers of the orpine and the wall- 

 pepper and their allies, however, that we find 

 preserved better than in any other dicotyledonous 

 plants, the original arrangements of five. Their 

 calyx usually consists of five sepals ; their corolla 

 of five petals ; their stamens of two whorls of five 

 each, and their pistil of five distinct carpels or 

 ovaries. 



Thus the flowers of the stonecrops, like their 

 leaves, have largely retained their primitive form, 

 and for the same reason ; namely, lack of com- 

 petition. Their comparatively simple life has not 

 necessitated complexity of structure in their floral 

 organs such as that adopted by some of their 

 neighbouring plants which have been continually 

 harassed by competitors in their struggle for 

 existence. At least, that is my reading of the 

 structural details of these rock -loving plants. 



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