bird, recently caught by the swell and thrown upon the shore, lying side by side with the remains of others that had previously succumbed to starvation—on every side evidence of the devastation wrought by the Atlantic. May not some of this destruction have been brought about by the nests having been placed upon the lower ledges within reach of an exceptionally heavy sea? Hence much depends upon the nature of the rock-formation, and many a mighty precipice, even though it may fulfil the first and third condition, is nevertheless valueless as a breeding station.
Finally, the young bird must occupy a ledge from which it can reach the water in safety. There is much difference of opinion as to the manner in which it leaves the ledge, but all agree that it does so before it is capable of sustained flight. If, then, the face of the cliffs were made up of a series of broken precipices, or if the rocks at the base projected out into the water, or if detached rocks abounded in the waters beneath, the mortality amongst the chicks would no doubt be considerable.
The coast-line of Co. Donegal will illustrate the foregoing remarks. On the southern and western side of the Slieve League promontory there is no real Guillemot station; only on the northern side—the quartzite in the vicinity of Tormore—are the birds to be found in large numbers. Northwards from here, a wild and rugged coast is passed over before other stations are reached—at the eastern end of Tory Island
