GULLS AND DIVERS 69 



watching, in that sharp way of his, to see that 

 nothing is carried back again. He may be 

 familiarly classified as our shore-gull. 



His black, or rather brown head would be a 

 sufficient mark, if it were constant. But then he 

 puts it on in the spring, and off in the autumn ; 

 so that he is without it during the greater part of 

 his stay at the seaside. In other words, it is his 

 bridal dress. He does not really put off the old to 

 put on the new. Therefore the rapidity of the 

 transformation. The feathers simply change their 

 colour. The effect is half a marvel. To-day he is 

 pottering about in his white head, without any 

 hint of what is to happen. To-morrow he appears 

 in a brown, so dark that in the distance it looks 

 black. It is as if nature had run a brush over 

 him in the nip;ht. 



O 



Both sexes change alike. This is not uncommon 

 among sea birds, and would seem to cast doubt on 

 the theory that the male alone makes himself gay 

 for the wedding. All it does show is that no 

 explanation will take in every detail. 



The change takes place about the twentieth of 

 March. For a few days longer the freshly-painted 

 gulls remain ; but, by the end of the month, the 

 sandbanks are deserted. 



