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laid during the last week of May. One lot brought off their 

 young successfully and laid again about the 7th of July. 

 The other pair had six eggs also in the last week of May 

 and were still sitting in the first week of July, that completing 

 their sixth week. All the eggs were addled during the 

 second week of incubation when the birds were disturbed by 

 visitors. 



In my opinion there were two hens sharing the nest. That 

 might even explain the fact that the birds incubated for 

 six weeks, for according to personal experience at least, 

 I find that a bird sitting on addled eggs deserts usually 

 within three days of her normal time. 



It appears to be a common habit with the Oystercatcher 

 when laying three eggs only, to pull in a large stone as com- 

 pensation. Whether this is coincidence or purpose it is hard 

 to say. (A similar case has been brought to my notice with 

 the Ringed Plover.) The third egg was already hatched 

 when the accompanying photograph was taken. W. Rowan. 



HERRING-GULLS DIVING. 

 On August 9th, 1913, I watched some adult Herring-Gulls 

 {Larus a. argentatus) diving for food in comparatively deep 

 water at the mouth of the river at Looe, Cornwall. Their 

 action resembled that of the Terns, for they completely 

 submerged themselves at every dive. This habit is probably 



