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18 THE LIFE OF THE PLANT 



are thoroughly perplexed as to where the sepals end and 

 the petals begin, so gradual and unnoticeable is the 

 passage from the hard green sepal to the delicate white 

 or red petal. So a petal is nothing but a modified sepal, 

 which in its turn is a modified leaf. It follows that a 

 petal is nothing but a leaf. 



Let us now peep into the inside of a flower, and choose 

 for our purpose one of the larger flowers, say a lily. 

 From the centre of the flower several organs project, 

 composed of a thin stalk, on the top of which are 

 inserted crosswise two yellow oblong sacks split longi- 

 tudinally. The slit discloses a dry dust, orange in 

 colour, the pollen. These organs are called the stamens ; 

 the receptacles containing the pollen are the anthers, and 

 the stalk bearing them the filament. One would think 

 that a stamen and a petal have no connection whatever. 

 But let us look for a suitable illustration before jumping 

 to a conclusion. Probably every one is familiar with 

 the white water-lily, so common in our streams and 

 ponds, with its large almost round leaves and its flowers 

 floating on the surface of the water. Let us pull one 

 of these white flowers to pieces and spread out its 

 several parts, as we did with the bud of the chestnut, 

 beginning with the outermost, i.e. the external white 

 petals, and ending with the part nearest the centre of 

 the flower, the organ, composed of the yellow receptacles 

 filled with pollen and a filament rather flat in form, in 

 which we easily recognise a stamen (fig. 9). We notice 

 once again the same imperceptible transformation : here 

 is a typical white petal ; on the top of it appear two 

 yellow spots, which increase in size as the base of the 

 petal becomes narrower ; two oblong receptacles become 

 clearly marked, and the base of the petal transforms 

 itself into a narrow filament. Here at last is a real 

 stamen, the anthers of which split longitudinally and 

 shed the pollen. The petal has passed into a stamen. 

 The possibility of such a transformation is proved 



