Bramble-bees and Others 



denly those powers burst forth, free of any 

 previous attempts, even as the spark poten- 

 tially contained in the flint flashes forth inde- 

 pendently of all preceding gleams. Could 

 one who knew nothing of the Sparrow but 

 her nest under the eaves suspect the ball- 

 shaped nest at the top of a tree? Would one 

 who knew nothing of the Osmia save her 

 home in the Snail-shell expect to see her ac- 

 cept as her dwelling a stump of reed, a paper 

 funnel, a glass tube? My neighbour the 

 Sparrow, impulsively taking it into her head 

 to leave the roof for the plane-tree, the 

 Osmia of the quarries, rejecting the natal 

 cabin, the spiral of the shell, for my cylinder, 

 alike show us how sudden and spontaneous 

 are the industrial variations of animals. 



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