206 SIGNS AND SEASONS 



I imagine the smaller birds have an enemy in 

 our native white-footed mouse, though I have not 

 proof enough to convict him. But one season the 

 nest of a chickadee which I was observing was 

 broken up in a position where nothing but a mouse 

 could have reached it. The bird had chosen a 

 cavity in the limb of an apple-tree which stood but 

 a few yards from the house. The cavity was deep, 

 and the entrance to it, which was ten feet from the 

 ground, was small. Barely light enough was ad- 

 mitted, when the sun was in the most favorable 

 position, to enable one to make out the number of 

 eggs, which was six, at the bottom of the dim inte- 

 rior. While one was peering in and trying to get 

 his head out of his own light, the bird would star- 

 tle him by a queer kind of puf5&ng sound. She 

 would not leave her nest like most birds, but really 

 tried to blow, or scare, the intruder away; and 

 after repeated experiments I could hardly refrain 

 from jerking my head back when that little explo- 

 sion of sound came up from the dark interior. One 

 night, when incubation was about half finished, the 

 nest was harried. A slight trace of hair or fur at 

 the entrance led me to infer that some small animal 

 was the robber. A weasel might have done it, as 

 they sometimes climb trees, but I doubt if either 

 a squirrel or a rat could have passed the entrance. 



Probably few persons have ever suspected the cat- 

 bird of being an egg-sucker; I do not know as she 

 has ever been accused of such a thing, but there 

 is something uncanny and disagreeable about her, 



