GREAT SHEARWATER. 289 



parts ; the bill, legs, and irides are dark brown, but the inner 

 side of the tarsi and webs are greyer. Length, 18 ins. Wing, 

 12 ins. Tarsus, 2 ins. 



Great Shearwater. Piiffijms gravis O'Reilly. 



So far the only known breeding place of the Great Shear- 

 water (Plate 126) is the Tristan da Cunha group in the south 

 Atlantic, though probably other stations exist. In our spring — 

 the southern autumn — the bird migrates north and occurs 

 throughout the Atlantic, even to the Greenland seas. Appar- 

 ently the northward movements of this oceanic bird are even 

 further from the shore than on its return, for in June and July 

 it is fairly frequent off the Outer Hebrides, St. Kilda, and 

 Rockall ; on June 22nd, 1912, Mr. R. W. Jones saw a large 

 shearwater, flying with the Manx Shearwaters, off the Orme's 

 Head, which from his description and the fact that he is 

 familiar with the smaller species, can only have been a Great 

 Shearwater, unless it was one of the much rarer forms of 

 P. kiihli. From August until November the Great Shearwater 

 appears with certain indications of regularity, slowly passing 

 south, but usually weU off shore ; it is commoner off the western 

 than the eastern coasts, though the Yorkshire records are so 

 frequent that it must be looked upon as an almost annual 

 autumn visitor. It looks dark on the wing, but its light under 

 parts, which show even when it is swimming, prevent confusion 

 with the Sooty Shearwater ; a dark tail-band and white upper 

 tail-coverts are conspicuous as it turns in true shearwater 

 flight. From the next species it may be told by its darker 

 bill, wings, and back. The flight resembles that of other 

 shearwaters, but it has been stated to have a rapid moult of 

 the flight feathers in June and July, when it is for a time help- 

 less. It is true that examples have been captured on the water, 

 but at this season they have^often been seen in full flight ; 

 further observations on this point are desirable. 



Series II. U 



