436 FORKED-TAILED PETREL. 



with its feet, probably on account of the shortness of its legs, although ic 

 frequently allows them to hang down. In this it resembles the Thalassi- 

 droma pelagica, and Wilson's Petrel has a similar habit during calm 

 weather. I have seen all the three species immerse their head into the water, 

 to seize their food, and sometimes keep it longer under than I had expected. 

 About the first of June, the species separate, collect in numbers, and 

 return to their breeding places. I state so from the report of persons on 

 whose testimony I can rely, and who have assured me that, like the Guille- 

 mots, they revisit their haunts each spring for years in succession. They 

 now fly in front of the high rocks, in the manner of our Purple Martin 

 when it first arrives at its well known box, passing and repassing a thou- 

 sand times in the day, enter their dark and narrow mansions, or stand in 

 the passage, and emit their cries, as the bird just mentioned is wont to do 

 on similar occasions. Now they alight on some broad shelf, and walk as 

 if about to fall down, but with considerable ease, and at times with ra- 

 pidity. Now and then the mated birds approach each other, and, I be- 

 lieve, disgorge some food into each other's mouths, although I am not ab- 

 solutely certain that they do so, having only observed them at such times 

 by means of a glass. They collect grasses and pebbles, of which they form 

 a flat nest, on which a single white egg is deposited, which measures an 

 inch and a quarter in length, by seven-eighths in breadth, is nearly equal- 

 ly rounded at both ends, and looks very large for the size of the bird. 

 When boiled, it has a musky smell, but is palatable. When you pass 

 close to the rocks in which they are, you easily hear their shrill querulous 

 notes ; but the report of a gun silences them at once, and induces those 

 on the ledges to betake themselves to their holes. 



The Forked-tailed Petrel, like the other species, feeds chiefly on float- 

 ing mollusca, small fishes, Crustacea, which they pick up among the float- 

 ing sea-weeds, and greasy substances, which they occasionally find around 

 fishing-boats or ships out at sea. When seized in the hand, it ejects an 

 oily fluid through the tubular nostrils, and sometimes disgorges a quantity 

 of food. I could not prevail on any of those which I had caught to take 

 food. 



These birds are caught from the sterns of vessels, with long slender 

 threads, the manner of vising which I shall describe when I come to speak 

 of Wilson's Petrel. I never could entice one of them to swallow a hook. 

 Very few are found on the coasts of England or Scotland, where, how- 

 ever, the species is said to breed. 



