IN THE GLOXINIA THE PETALS ARE ALL JOINED. 



CHAPTERS IN PLANT LIFE 



VIII— THE EVOLUTION OF THE FLOWER 



By S. LEONARD BASTIN 

 With Photographs by the Author 



IX a general way, without the system 

 of organs to which has been gi\'en 

 the name of flower, the blossoming 

 plants could not continue to exist. Of 

 course, there are exceptions where plants 

 producing flowers are not entirely de- 

 pendent upon the offices of the floral 

 organs for the per]:)etuation of their kind. 

 N'aturally. all annuals rely entirely u])on 

 increase by seed, but there are a few 

 known cases in which perennial plants 

 have persisted in a locality, and extended 

 their field of growth, without ever ha\'ing 

 been known to propagate their kind 

 through floral agency. The most singu- 



132 I04I 



lar instance on record is that of a little 

 Oxalis introduced into Malta from the 

 Cape before the year 1804. The species 

 has spread along the shore of the Mediter- 

 ranean by means of bulbs, but has never 

 yet been observed to set seed in Europe. 

 A more homely instance of a plant which 

 is })ractically non-seeding is to be found 

 in the Lesser Celandine — a s])ecies which 

 only on the rarest occasions produces fertile 

 seed. The common mode of increase 

 adopted by tliis ])lant is to be observed 

 if the a.xils of the leaves are examined just 

 after flowering time. In each recess 

 there will be found a curious little tubt-r 



