LEACH'S PETREL. 281 



dusk from incubating- birds in the holes. This churr often ended 

 in a sharp wit. Nearly two hours after sunset the birds 

 emerged and flitted round in the dusk. Dr. Eagle Clarke found 

 one colony deserted in the daytime, for the young were hatched, 

 and concluded that the birds go off for food during the day and 

 feed the young at night ; the food is regurgitated oily matter, 

 probably half-digested squids. An oily smell pervades the 

 colony, and the bird itself reeks of oil ; if handled its first act of 

 retaliation is a jet of oil, squirted from beak or nostrils. The 

 down of the sooty brown nestling is long [and on the under 

 parts hoary, its bill and legs are at first white, but soon darken. 

 There is little difference between young and adult birds, though 

 the slight white wing bar is perhaps more noticeable in the 

 former. The bill and legs are black, the irides blackish brown. 

 Length, 6 '5 ins. Wing, 47 ins. Tarsus, 0*9 in. 



Leach's Petrel. Oceanodroma lencorrkoa (VieilL). 



The North Atlantic breeding range of Leach's Petrel (Plate 

 123) is more to the north and west than that of the Storm- 

 Petrel, and it also occurs in the north Pacific ; the only known 

 European stations are in the British Isles — on St. Kilda, the 

 Flannans, North Rona, and a few islands off the west coast of 

 Ireland. Yet the bird, on the whole, is more frequently seen off 

 our shores, for a number pass south in autumn over our seas ; 

 westerly gales often drive them inshore, and not infrequently 

 whirl them helplessly far inland. As a derelict it is not un- 

 common, even at a distance from the coast. 



The full name is Leach's Fork-tailed Petrel, for it is the 

 decidedly forked tail which distinguishes it from the Storm, 

 though not from all its congeners. It is larger, but in the 

 main its sooty dress and white back patch agree with those 

 of the last species ; the median wing-coverts are pale brown, 

 and show on the flying bird, as Mr. R. W. Jones points out, as 



