Summary.1Notes on the history and former fowling of the Rock Dove on Nolsoy, Faeroe Islands, are given.2The population (normally 50–60 pairs) is polymorphic, the mutants showing a tendency towards melanism and having mantle and wing‐coverts spotted black. These occur in the ratio 1: 7 of the normal type when the population is at its peak, but seem less able to survive a severe winter, so that the proportion falls steeply to 1: 15–20 birds. The existence of polymorphism is noted in other widely‐separated populations, and the incidence of the partial melanism is discussed in the light of data available for 19 broods. The character is thought to be recessive, and more than one gene may be concerned.3Nesting‐sites are described and observations on the breeding‐biology are given, comparisons being drawn with Lees' work on Cromarty birds. Breeding is confined to the summer and is not spread over the whole year (as in Cromarty), and two broods of two young, with a very low mortality, are usual. Young remain on or near the nest for five weeks, but are not tolerated near the new nest by the parent if a second clutch is being incubated. Otherwise they are accompanied and fed for several days after fledging.4Flocking, roosting and feeding habits and bathing procedure are described; stomach contents for April–May, May–September and December–March are noted, seeds ofRutnexproviding much of the food. The population is greatly reduced by severe winter weather, and is now (1947)