The Eggs of Birds 



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—one end blunt and narrowing to the other— tluit they 

 have given to it its name: ovah In the eggs of certain 

 sea-birds which breed on the narrow ledges of perpen(li(;ular 

 cliffs this oval shape is carried to an extreme, and aj)- 

 parently for an excellent reason, mechanical, but of ines- 

 timable value to the birds. Eggs laid in such positions 



Fig. 34;1— Egg of Murre. 



are of course especially exposed to danger from the wind 

 or from some sudden movement of the birds, which gener- 

 ally nest very close together. Were it not that the eggs, 

 on account of their peculiar shape, describe an arc of 

 very small diameter when they roll, doubtless a far greater 

 number would roll off and be dashed down uj)on the 

 rocks below. Among the plovers, sandpipers, and phal- 

 aropes we again find a peculiarly pronounced pjTiforni 



