Birds of Britain 



duriug tlie breeding season at all events, only leaving their 

 retreat after dark and returning before dawn, so that it is 

 very difficult to detect their presence. The sitting bird, 

 however, utters a curious note while sitting, and a strong 

 musky odour pervades the burrow, so that by this means 

 the nest may frequently be found. If handled, the bird 

 emits a greenish oil. 



In England it only nests sparingly on the coast of Wales 

 and in the Scilly Islands, but in Scotland and Ireland its 

 breeding places are numerous. 



The adult is sooty black all over, but the bases of the 

 tail coverts are white and the edges of the wing coverts are 

 slightly edged with white. Length 6*5 in. ; wing 4*7 in. 



LEACH'S FORK-TAILED PETREL 



Oceanodroma leucorrhoa (Vieillot) 



This species is a regular but not very numerous visitor 

 to our shores every autumn, its numbers depending largely on 

 the weather, and after heavy gales it is often found inland. 

 It nests in small numbers on St. Kilda and some of the 

 Outer Hebrides, and has also been found nesting off the 

 coast of Kerry ; and in time many other breeding stations 

 will probably be found on the islands of our western shores. 

 The single egg is white freckled with rusty spots. In its 

 food and Babits it resembles, so far as they are known, those 

 of the Storm Petrel. 



The adult is dark leaden black, rather more sooty below ; 



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