MOORLAND IDYLLS. 



I know of structures begotten by long 

 functional use, and perfected by the action 

 of natural selection. It is not only that the 

 bill is a most admirable and efficient boring 

 instrument ; it is not only that the tongue 

 is capable of rapid and lightning-like pro- 

 trusion ; but further still, the barbs at its 

 ends are all directed backward, like the 

 points of a harpoon, while the very same 

 muscles which produce the instantaneous 

 forward movement of the tongue press at 

 the same time automatically on two large 

 salivary glands, which pour forth in response 

 a thick and sticky secretion, not unlike bird- 

 lime. The insect, once spotted, has thus no 

 chance of escape ; he is caught and devoured 

 before he can say "Jack Robinson" in his 

 own dialect. 



But though the green woodpecker is so 

 exceedingly practical and sensible a bird, 

 built all for use and very little for show, he 

 is not wholly devoid of those external adorn- 

 ments which are the result of generations of 

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