238 STUDIES IN BIRD-MIGRATION 



that he received an adult specimen which had been 

 obtained on 7th May 1903. 



* Larus leucopterus, Iceland Gull. — An immature 

 example, captured in March 1903, was forwarded to Dr 

 Wiglesworth. This is the only known instance of the 

 occurrence of the species. 



Larus fuscus, Lesser Black-backed Gull. — 

 MacGillivray (p. 59) includes this Gull among the species 

 seen by him in July 1840. It is not, however, mentioned 

 by Wilson, an accomplished naturalist, who visited the 

 islands in the spring of the following year. Milner (pp. 

 2059-2062) tells us that in June 1847, the Greater and 

 Lesser Black-backed Gulls were breeding on Dun in 

 abundance. Dixon (p. 86) says that it breeds in 

 considerable numbers on St Kilda and the adjoining 

 islands and stacks ; but Steele Elliot (p. 95), Wigles- 

 worth (p. 41), and others, have been quite unable to find 

 it anywhere in the archipelago during the nesting 

 season. 



In 191 1, however, I heard that this species bred at 

 St Kilda during the summer. A single nest, with 

 Gggs, was found by Neil Ferguson, who told me that 

 this is the only instance known to him of this Gull 

 having bred on any of the islands of the St Kilda 

 group. 



We were always on the look-out for this species, but 

 were only rewarded by seeing two birds of the year, in 

 company with two young Herring-Gulls, on the sand at 

 the head of the East Bay on ist September 19 10, and 

 another on loth September 191 1. 



Larus marinus. Great Black-backed Gull. — This is 

 the largest form of " Sea-Mall " mentioned by Martin 

 (p. 63) as inhabiting St Kilda in 1697, to which he 



