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disappearance of the eggs, and was so like the work of a shrew 

 that I had little doubt as to its origin. 



During the spring and summer of 1907, I kept the eggs 

 and young of several species of ground-nesting birds under 

 close observation. A number of nests of such birds were found, 

 and photographed, and subsequently visited at frequent inter- 

 vals in order to note any signs of molestation by shrews or mice. 

 In two instances nests were robbed in such a manner as to indi- 

 cate the work of shrews. One of these nests also was that of a 

 black and white warbler, and in this case was located beneath 

 a small, overhanging stone in the same woods as the one de- 

 scribed above. When first found it contained two half-fledged 

 birds. The nest was at once photographed, and a week later 

 was revisited, when the young birds were found to have disap- 

 peared. By turning back the mass of dead leaves about the nest 

 a distinct burrow was found approaching it from beneath and 

 penetrating the bottom. It is possible that at the time the nest 

 was disturbed the birds might have attained size enough to 

 have escaped their enemy by flying, but be this as it may, some 

 little mammal had undoubtedly made an attempt upon them. 



The other case was that of a whip-poor-will, Antrostomus 

 vociferous, whose two eggs were found in the woods on a bed of 

 forest leaves on June 14th. The eggs were photographed and 

 within twenty-four hours afterward some little mammal mined 

 up through the leaves directly under the eggs and broke both 

 of them, devouring the contents and most of the shells. A 

 mouse-trap was forthwith set at the opening, and two days later 

 a shrew entered the trap and was caught. This seemed to estab- 

 lish a pretty strong case against the shrew. It is worth men- 

 tioning, however, that the next night after the trap was set a 

 mouse of some kind visited it and left several pellets of excre- 

 ment on the wood piece that held the wire mechanism together 

 The broken birds' egg that served as bait was taken, but the 

 trap was not sprung. The excrement was evidently that of a 

 white-footed mouse, certainly it was not that of a shrew, as 

 there is a marked difference in the appearance of the excrement 

 of the two animals. The act of the mouse in visiting the spot 



