The vegetation of this isolated island, from which the inhabitants and their sheep have recently been removed, is described fully, as a starting point for observations on the changes involved in a return to natural conditions consequent upon the cessation of grazing and cultivation. The principal vegetation is moorland dominated by Festuca ovina and Nardus stricta Calluna vulgaris is present, but dwarf, and may develop now grazing has ceased. Modifications are brought about by the sea spray which reaches to 300 ft. above sea level, and by the extensive puffin colonies. Vegetation around these is of a rank nature resembling that of formerly cultivated areas. Nitrogenous manuring seems the important factor in both cases.