16 THE ZOOLOGIST. 



35. Herring-Gull {Larus argentatus). — Breeding in considerable 

 numbers at the foot of the mountain, on the shelving rocks over the 

 sea. I think a few pairs breed in the breastwork of rock about the 

 south point and the south-west side. 



36. Great Black-backed Gull (L. marinus). — One pair had a nest 

 and three eggs near the Herring- Gulls. 



37. Razorbill (Alca torda). — I only saw two or three at the foot of 

 the cliffs. They are said to breed in one inaccessible spot. 



38. Guillemot (Uria troile). — About a score or more with the 

 Razorbills. Probably the breeding-place is somewhere about the 

 north-east corner. I do not think there can be many birds of either 

 species there ; for, although Razorbills began laying in another breed- 

 ing-place in Lleyn at this date, no Guillemot's egg was seen until a 

 day or two later, although the birds were sitting about the ledges. The 

 proportion of Bardsey birds presumably on the cliff, and not seen by 

 me, to those on the water would probably not have been large. 



39. Manx Shearwater [Puffinus anglprum). — There is a consider- 

 able colony at the north-east end of the island, on the side of the 

 mountain. When I left the breeding-place, about 9.30 p.m., all was 

 quiet ; but about midnight I could hear numbers crying incessantly 

 "cock-cock-go-grow," or "cock-go-grow," over the fields in front of 

 the house I was sleeping in. And one of my boatmen, who was 

 coming along the road about that time, said that, although it was too 

 dark to see them, they appeared to be flying about over the fields, low 

 down. They breed chiefly on a steep grassy cliff varied by patches of 

 fern, and large rocks which project from the turf. Some of the Shear- 

 waters breed in holes under these rocks where they emerge from the 

 turf; others in long clefts in, and winding passages among, the rocks. 

 Most of the birds and eggs are quite inaccessible, but certain marks at 

 the entrance denoted an occupied hole. Some of the birds were in- 

 dignantly noisy when a stick was gently pushed into the easier holes. 

 We extracted two birds and an egg from burrows. The birds are very 

 savage, and bite everything within reach, and they inflict a painful 

 bite. Another egg we could see in a cleft in the rocks, but could not 

 reach. In one place there was a little cave under some rocks, and in 

 it on the bare earth floor we could see an egg. The entrance of the 

 cave was large enough, when a sod had been pulled away, for a young 

 boatman to wriggle in on his stomach and fetch the egg ; inside the 

 cave was large enough for him to turn in. The bird must have retired 

 to some inner fastness. Both the other eggs lay on the bare soil. As 

 far as I have seen the ground immediately in front of holes selected by 

 Shearwaters to breed in always falls very sharply; indeed, in some 



