PETRELS. 249 



many writers. The Fork-tailed Petrel is known 

 to breed on North Rona, and at some other spots 

 in the Outer Hebrides, as well as on the Blaskets 

 off the coast of Kerry. There can be little doubt 

 that many other breeding stations of this Petrel 

 remain to be discovered. This species, readily dis- 

 tinguished from the Stormy Petrel by its larger size 

 and deeply-forked tail, is rarely seen near the land 

 unless during the breeding season, or when driven 

 thence by boisterous weather. I have known it 

 to be caught in the flight-nets on the mud-banks 

 of the Wash ; whilst it is of tolerably frequent 

 occurrence elsewhere off our eastern and southern 

 coasts. In its habits generally it very closely 

 resembles its better known ally, the Stormy Petrel. 

 During the non-breeding season it wanders vast 

 distances from land, sleeping and resting on the 

 sea when tired, following ships for miles, fluttering 

 along close to the ocean, now down into the trough 

 of the wave, anon skimming over the crest to half- 

 fly, half-run, with patting feet, down the smooth 

 surface of the next. Except during the breeding 

 season this Petrel is not very gregarious ; it may 

 often be seen in parties of perhaps half-a-dozen, 

 scattered over a considerable surface of water. The 

 exact nature of the food of this species is apparently 

 unknown. It is said, in a vague and general way, 

 to feed on crustaceans and small molluscs, and the 

 scraps of refuse cast from passing vessels, but birds 

 which I have dissected contained similar substances 



