SAND DUNES AND SALT MARSHES 



parents, who rarely alight on the water, 

 watched them from the shore. Possibly here 

 was an explanation of the value to terns of 

 webbed toes. Functionless in the adult, they 

 are of service to the young before the power 

 of flight is acquired.'' In this supposition he 

 is probably right, although this service to the 

 young is not the reason for the existence of 

 the webs, but the observation points very 

 clearly to the swimming ancestry of the 

 birds. We could not have stronger proof of 

 it. 



That the auks are out and out water birds 

 there needs no defense, but one is at first sight 

 puzzled by the presence of the pigeons in this 

 group. The older systematists placed the 

 pigeons with the partridges and the domestic 

 fowl tribe, but pigeons may be seen wading 

 in puddles in a manner that would alarm the 

 barnyard cock. I have been told by a pigeon 

 fancier that young pigeons are much attracted 

 by water and fond of bathing therein, and that 

 young birds are liable to drown themselves in 

 tanks or troughs if these are accessible to 

 pigeon lofts. A fact of considerable interest 

 in this connection is that a pigeon with per- 

 fectly webbed feet has been evolved by only 



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