NOTES ON THE MA3H1VIALS AND BIRDS OF ROUSAY. 67 



Red-breasted Merganser (Mergus serrator). Com- 

 mon throughout the year, and although I never saw 

 a nest, they must breed in considerable numbers, 

 especially on some of the small outer islands. I 

 have seen large flocks of them early in June ; per- 

 haps some of these would be young non-breeding 

 birds. They are extremely wary. The old males 

 had assumed their full plumage by about the third 

 week in November. 



Pygopodes. 

 Fam. Colymhiduj. 



Great Northern Diver (Colymhus glaclalis). I 

 saw the first "Imber" of the season, a bird appa- 

 rently in full summer plumage, on loth October. It 

 rose within twenty-five yards of the steamer, and 

 appeared but little alarmed. They are very common 

 birds here, generally three together— two old and 

 one young one. They have the same habit as the 

 Black-throated Diver of lying on their sides in the 

 water and showing their white breasts. Their cry is 

 a loud and cheery laugh, bringing to me pleasant 

 associations of the Canadian lakes, where often this 

 is the only living creature to be seen or heard. 

 There, too, I never observed them to be accom- 

 panied by more than one young one. 



Black-throated Dixeh (Colymhus arc ficus). There 

 was one pair to be seen pretty constantly in May 

 and early in June on two lochs not far from West- 

 ness House. I often saw pairs of these birds late on 

 in July on these same lochs, apparently migrating, 

 as they never stayed long at a time. Constantly in 

 the evenings at the end of July and early in August 

 I used to hear and see these birds, or the red-throated 

 species, flying oa er the island, taking a S.W. course, 

 almost always in pairs. Do the old birds leave first, 

 allowing the young ones to follow later on? 



These Divers all seem to leave their breeding 

 quarters about the same time. In Sutherland, where 

 they are very common, I never remember seeing any 



