IN FIELD AND WOOD 



doing. Then I investigated and found the nearly 

 fledged birds all dead. On removing them I found 

 the nest infested with many dark, tough-skinned, 

 very active worms or grubs nearly an inch long, that 

 had apparently sucked the blood out of the bodies 

 of the fledglings. They were probably the larvae of 

 some species of beetle unknown to me. The parent 

 birds had looked on and seen their young destroyed, 

 and made no effort to free the nest of their enemy. 

 Or probably they had not suspected what was going 

 on, or did not understand it if they beheld it. Their 

 instincts were not on the alert for an enemy so 

 subtle, and one springing up in the nest itself. Any 

 visible danger from without alarmed them instantly, 

 but here was a new foe that doubtless they had 

 never before had to cope with. 



The oriole in her nest-building seems more fickle 

 than most other birds. I have known orioles several 

 times to begin a nest and then leave it and go else- 

 where. Last year one started a nest in an oak near 

 my study, then after a few days of hesitating labor 

 left it and selected the traditional site of her race, 

 the pendent branch of an elm by the roadside. 

 This time she behaved like a wise bird and came 

 back for some of the material of the abandoned 

 nest. She had attached a single piece of twine to 

 the oak branch, and this she could not leave behind; 

 twine was too useful and too hard to get. So I saw 

 her tugging at this string till she loosened it, then 

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