i6 



The Bird Rock Group. 



family Alcidae, a group of sea-birds found only in the North 

 Atlantic and North Pacific. (Several allied species may be found 

 in the general collection of North American Birds, see gallery, 

 Case A.) Everywhere they are island-nesting birds, indeed some 

 of the largest bird islands in northern seas are inhabited almost 

 entirely by Murres:— the Fame Islands off the eastern coast of 

 northern England, the Farallones at the entrance of San Francisco 



COMMON MURRE AND EGQ. 

 From the Group. 



Bay, and St. Paul Island in Bering Sea, are tenanted by countless 

 individuals of these birds. Murres feed on fish, which they se- 

 cure by diving, using both wings and feet in propelling themselves 

 while under water. Their note is a hoarse call sounding somewhat 

 like the syllable i7iurre, whence their common name. They make 

 no nest, but lay their one peculiarly shaped and colored egg on an 

 exposed ledge of rock or in a similarly unprotected place. The 

 shape of the egg is supposed to be an adaptation to the require- 

 ments of the nesting sites, from which a more elliptical or spheri- 



