58 



Case 228 — continued. 



BLACK TEEN {Hydrochelidon nigra). 



A passing migrant. Few local records — one at Ashton-on-Mersey 

 November 3, 1893 (" History of Lancashire," p. 203). 



IVORY GULL {Pagophila eburnea). 



This species appears on the Northern coasts when severe winters 

 have driven it from Spitzbergen and the neighbourhood. Locally it is 

 said to have been killed on several occasions in Morecambe Bay (?), 

 and one was taken at Kendal and one at Carnforth (" Fauna of Lake- 

 land," p. 438). 



GLAUCOUS GULL {Lams glaucus). 



This species is the " Burgomaster " of the whalers. It is distin- 

 guished by its enormous spread of wings, being one of the largest of the 

 gulls. It is only an irregular visitor, and very rare to this locality. 



POMATORHINE SKUA {Stercorarius pomatorhinus) . 



A passage-migrant and winter visitor. It fairly regularly makes 

 its appearance in the district. 



POMATORHINE SKUA and COMMON GULL. 



These specimens were shot in the Mersey in the circumstances 

 shown in the case. While in flight the Skua is forcing the Gull to release 

 its freshly-caught prey, which the Skua in turn by a sudden dive catches 

 before it reaches the sea. 



GREAT SKUA {Megalestris catarrhactes) . 



This species is resident in the Shetlands. It is locally known as 

 the " Sea Hawk," and not a common visitor to this district. For eggs 

 see Case 231, drawer B. 



RICHARDSON'S SKUA {Stercorarius crepidatus). 



A summer resident and passing migrant. Not uncommon locally. 

 For eggs see Case 231, drawer 23. 



BUFFON'S SKUA {Stercorarius parasiticus). 



Irregular autumn migrant, locally a rare visitor. For eggs see 

 Case 231, drawer 33. 



LITTLE GULL {Larus minutus). 



Irregular autumn and winter visitor. It has been seen on rare 

 occasions in this district during the winter. 



