times. With the aid of the glass, I made out (judging from the birds on the sea) that there was about one Razorbill (easily distinguished by its neater shape, head drawn back and tail raised, from the paler and browner Guillemots) to every six or eight of the latter birds. A few Razorbills breed on St. Tudwal's, and at the date of my visit were sitting on eggs in shallow cracks and covered ledges for the most part, but one or two were on open ledges. They all occupied detached places, and did not sit two or three close together like Guillemots. In every case but one the birds sat or lay on the eggs in a semi-horizontal position; the exception was half upright, but, as I could see its eggs, it was probably alarmed. When sufficiently alarmed they shuffled their eggs from under them, stood up, and dropped off the ledges. As Mr. Coward found Razorbills plentiful at sea near Nevin, they probably breed on the north coast also. As to the Manx Shearwater, I am unable to add anything of importance to what Mr. Coward has already recorded in 'The Zoologist.' There is, however, no doubt that "Mackerel Cocks" breed on the mainland, and some of the islands of western Lleyn. This is not surprising when we remember that a great breeding haunt of this species lies off the southern horn of Cardigan Bay. I saw remains of two or three dead birds, and when off in a boat one morning saw five skimming low over a rather lively sea; but they are chiefly nocturnal. They strike the light sometimes, and flutter down into the court. They are very stupid, and make no attempt to escape, but fly away when thrown up into the air. I was told that when the Mackerel come into one of the bays in July and August lots of Shearwaters were seen over the shoals.
I have only to add that this paper applies to the western part of the Carnarvon promontory, and that it is offered as a small instalment towards the history of the Birds of North Wales. During the spring of 1900 I hope to continue my observations.
