MONKSHOOD. 



339 



sideways from a spike are very apt to become bilaterally 

 symmetrical ; indeed, whenever they are not so, one 

 can always give an easy explanation of their deviation 

 from the rule. Probably the blossoms of the monks- 

 hood began by arranging themselves in a long and 

 handsome spike, so as more readily to attract the eyes 

 of insects, and that was the real starting point of all 

 their subsequent modifications. Or, to put the same 

 thing more literally, those moiikshoods which happened 

 to grow spike-wise succeeded best in attracting the 

 bees, and therefore were most often fertilised in the 

 proper manner. Next, we may suppose, the large 

 green sepals, being much exposed to view, began to 

 acquire a blueish tinge, as all $he upper parts of highly 

 developed plants are apt to do ; and the bluer they 

 became, the more conspicuous they looked, and there- 

 fore the better they got on in competition with their 

 neighbours, especially since bees are particularly fond 

 of blue. As each bee would necessarily light on the 

 middle or lower portion of the flower, he would begin 

 by extracting the honey from the two upper petals ; 

 but it would be rather awkward for him to turn round, 

 head downward, and suck the nectaries of the three 

 bottom ones. Hence, in course of time, especially 

 after the flower began to acquire its present shape, 

 the two top petals became specialised as nectaries, 

 while the three lower ones gradually atrophied, since 

 the coloured sepals had practically usurped their 

 attractive function. But as the flower can only 

 succeed by being fertilised, all these changes must 



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