ii RIVERSIDE LETTERS 7 



made in the twenty-second letter as to the 

 gulls which my wife and I saw feeding with 

 the rooks on the flooded meadows opposite our 

 house. I wrote : " They were probably the 

 small black-headed gull, which at this time oj 

 the year lose their black caps ; at any rate, 

 these had white heads." The words in italics 

 constitute my blunder. I knew that a change 

 took place in the colour of the head at that 

 season, but had reversed, in my mind, the 

 order of the change at the time I wrote ; the 

 fact being that the birds in the spring change 

 their white caps for black ones. I still 

 believe, however, that the gulls we saw were 

 the so-called "black-headed gulls" in their 

 winter plumage. My critics were, I think, in 

 error as to the date of the occurrence, thinking 

 it took place on the icth of April, the elate 

 when the letter was written, whereas I wit- 

 nessed the scene on the 2 2nd of March. 

 Now it is quite possible that, owing to the 

 severe return of winter, which took place in 

 March, 1889, mentioned in the preceding 



