The Barberries 



is fine, but close when the weather is bad. This is a 

 very unusual way for a pollen case to open, and it can 

 easily be seen by the aid of a hand lens. The six 

 stamens are arranged round a seed-case containing 

 many tiny ovules, which ovary supports a reddish 

 stigma disc upon a thick column. 



The stamens lean backwards so that they are almost 

 hidden in the petals' hollows, but if one takes a pin 

 and just touches one somewhere on the inner side 

 near the base of the filament, that stamen will promptly 

 raise itself and stand upright. If one lays the pin 

 across several together, they will act in unison and 

 close in round the style and stigma. (N.B. a flower 

 must not be too old or this pretty little experiment 

 may fail.) So when insects such as flies, bettles, bees 

 and wasps come searching for the honey that overflows 

 from the yellow nectaries and lies round the base of 

 the stamen filaments, they are bound to touch with 

 foreleg or proboscis the sensitive surface, upon which 

 the stamen promptly raises itself out of its dry security 

 in the petal concavity, and deposits its pollen upon the 

 unsuspecting stimulator. As the stamen moves up- 

 wards the insect moves towards the stigma, and hence 

 its head comes between the stigma and pollen and 

 effectually keeps them apart. Therefore the flower does 

 not fertilise itself, in spite of the fact that in all the 

 Barberries the stigma is mature and in a receptive 



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