LIFE HISTORIES OF FAMILIAR PLANTS 



Furthermore, there is the consideration of 

 colour in the flower-heads of the clovers. The 

 progenitor of the Pea-flower family doubtless had 

 yellow blossoms, and this colour, as Grant Allen 

 demonstrated so ably, is the lowest and most 

 primitive colour of flowers ; white, pink, red, 

 purple, and blue representing the order in which 

 floral colouration was evolved. Now, amongst 

 British pea-flowers yellow and orange reds are the 

 predominating hues. Here and there in the 

 various genera a species has progressed sufficiently 

 to produce pink or blue-tinted flowers, but it is in 

 the clovers that we find a complete evolution from 

 the family yellow through white, pink, red, and 

 purple stages. The latter colour is a favourite 

 with the bees, insects for which the clovers par- 

 ticularly lay themselves out when uniting their 

 petals into a narrow tube. 



It is now, I think, fairly clear that the clovers 

 have, like the wild camomile, by continual adap- 

 tation acquired blossoms specialised both in form 

 and arrangement to meet the convenience and 

 requirements of their particular insect guests. 

 The little flowers begin to mature with the outer- 

 most whorl, the inner whorls then succeeding just 

 as in the daisy type of inflorescence ; and the bee 

 quickly works around amongst the ripe flowers, 

 sucking up their sweet nectar and at the same 

 time conveying to the stigmas the pollen it has 

 brought from the flowers of other heads it has 

 previously \isited. Naturally, the bee fully ap- 

 preciates this arrangement of flowers which permits 



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