302 OUR RARER BIRDS 



a quantity of oil like that ejected by the Fulmar. Most 

 of this oil comes from the mouth, but a little oozes from 

 the tubular nostrils. We discovered nest after nest of 

 this bird, all in the holes. In two holes we found a bird 

 but no egg; they had probably gone into this retreat to 

 pass the hours of daylight, or they had not yet commenced 

 laying. In one hole there was an egg and no bird ; but I 

 believe the Petrel escaped by another of the several en- 

 trances. I never found more than one bird on the nest. 

 The nests vary a good deal in size, some being composed of 

 several handfuls of material, others of only a few straws, whilst 

 in one case no nest at all had been made, and the egg lay on 

 the bare ground. They are made of dry grass, a scrap or two 

 of moss, rootlets, and a few bits of lichen from the rocks. 

 The holes varied considerably in length, some being only two 

 feet, others as many as five feet ; but as they are made in soft 

 peaty soil it is a very easy task to unearth the nest. In some 

 cases the hole had several entrances, and then I found it 

 necessary to stop all up but one before beginning to dig out 

 the nest, thus preventing the parent from escaping until I had 

 examined her. I here observed that the holes which contained 

 Petrels' nests had a little dry grass at the entrance. Many 

 nests are placed close together an underground colony in 

 fact and I found half a dozen within a radius of eight or nine 

 yards. When, the little captive Petrels were released, they 

 flew about for a few moments in a very erratic manner, as if 

 dazed by the light, and then darted off. Some flew round 

 and round with rapid beats of their long wings, very much 

 like a Swallow or a Swift, and finally disappeared far out to 

 sea behind the distant rocks. 



The Fork-tailed Petrel lays only one egg, which differs 

 little save in size from that of the Stormy Petrel. Perhaps 

 the fine markings are a little larger and more decided, and 

 the egg is half as big again as that of the smaller species. 



