162 STUDIES IN BIRD-MIGRATION 



appear from more northern climes on their way south- 

 wards. 



A number of ducks, with broods only about one-third 

 grown, are always to be seen in September. During 

 the same month many of the adult males are in a variety 

 of piebald plumages — i.e., in various mixtures of post- 

 nuptial and winter dress. 



On 2 1st March 191 1, about three hundred were 

 seen in a flock. 



SoMATERiA SPECTABiLis, King Eider. — I saw an adult 

 male on the wing crossing the south bay on 13th May 

 1910. 



CEdemia nigra, Common Scoter. — A few single birds 

 have come under notice on the following occasions : — A 

 male on 22nd May 1910; and males on 5th and 9th 

 September 1907. 



CEdemia fusca, Velvet-Scoter. — Has thrice been 

 known to occur. An adult female was obtained on ist 

 December 1906 ; an old male on 17th September 1907 ; 

 and two examples on 20th October 19 10. 



Mergus serrator. Merganser. — This species is not 

 unfrequent, and seeks the heads of geos and the bays, 

 where it is to be seen during both the seasons of passage, 

 and where a few also remain all winter. 



In spring, arrivals have been recorded at mid-March, 

 but the bird is most frequent during May. It has 

 once been observed as late as the 14th of June. 



The earliest record for its appearance in autumn is 

 for 3rd September, and the migrants continue to pass 

 throughout the month and during October, usually in 

 small parties of from three to five, but sometimes singly. 



Ardea cinerea. Heron. — The Heron is observed 

 regularly in both spring and autumn as a bird of 



