446 BRITISH BIRDS. 



habits, and keeps close to its hole during the day. The egg is incubated 

 by both parents, for I took male and female birds from the nests, but, 

 as previously stated, I never met with two birds in the same hole. 

 Most of the nine eggs I obtained were quite fresh, but three of them 

 were slightly incubated. When I dissected the Petrels we caught, I 

 found the stomachs to contain an oily substance mixed with little bits 

 of sorrel. We now left the Petrels and explored the remainder of the 

 island with its swarms of birds. Donald snared a score or so of Puffins 

 with his rod, passing the noose very skilfully over their heads as they sat 

 unsuspiciously on the rocks. We obtained half a boat-load of Razorbills', 

 Guillemots', and Gulls' eggs, and then returned with our booty to the 

 slippery landing-place. The swell was rising fast, and we were anxious to 

 get away, for we had no desire to be imprisoned there for days, as is some- 

 times the case, the sea rising so fast as to prevent any boat approaching the 

 rocky shore. Donald told me that this Petrel is one of the earliest birds 

 to come in spring, and one of the last to leave in autumn." 



The breeding-colony of the Fork-tailed Petrel on the island of North 

 Rona, one of the Hebrides, was visited by Mr. John Swinburne on the 20th 

 of June, 1883. He found the birds breeding in burrows under and amongst 

 the walls of some ruins. He dug out twenty-three nests in about an hour 

 and a half, and could have obtained many others had he been inclined. He 

 noticed that the birds breed in small colonies, and that in some cases one 

 large main burrow in the walls of the ruins branched out at right angles 

 into several other holes, each containing nests. 



Brewer found this Petrel breeding in considerable numbers on a small 

 island in Fundy Bay in a plantation of spruce and birch. The nests were 

 in holes amongst the thick network of roots, which he had great difficulty 

 in cutting away so as to reach them. The birds had only just begun to 

 lay on the 24th of June. The following summer he visited the Green 

 Islands further up the bay. Here there were no trees ; the ground con- 

 sisted of soft black mould, covered with grass, and honeycombed with the 

 burrows of the Petrel. Many of the burrows were five feet long, twisting 

 and twining in every direction, so that sometimes the nest was under 

 the entrance to the long winding passage. In every case he found the 

 male on the egg, and when caught they ejected through the nostrils a 

 strong pungent musky oil of an orange colour. No mention is made of 

 any nest ; but Dresser quotes the account of the visit of Mr. G. A. Board- 

 man to some islands on the American coast of the same bay, in which the 

 burrows are compared to those of the Sand-Martin " under the sod/' whilst 

 others are dug under rocks. The passages are described as from two to 

 three feet long, and as ending in a nest loosely put together of fine grass, 

 with occasionally a few loose pebbles. A low note like peer wit was con- 

 stantly heard in all directions, uttered by the birds in their holes. 



