256 THE BIRDS OF IONA AND MULL. 



by a white line, which also encircles the eye ; there is besides a slight 

 difference in the tint and shape of the bird, which is only observable 

 when the two varieties lie side by side. 



The Black Guillemot. 



Norse, Tobis gripla. 

 Though the common guillemot rears but one young one, and this 

 bird rears three, yet it is infinitely less numerous ; nor is it a gregarious 

 bird, though to a certain extent it is migratory. It is usually found 

 solitary, or swimming in pairs, on the wildest and most rocky parts of 

 our coast, utterly regardless of the dreadful surf tumbling in white 

 cascades off the jagged rocks when the heavy swell of ocean heaves 

 downwards. The black guillemot is a very pretty and interesting little 

 bird, quite tame, allowing a close approach by boat. Its plumage 

 undergoes an extraordinary seasonal change, so that in spring and 

 autumn two birds will not be found exactly alike, its colours ranging 

 through every shade of grey, from white, speckled, piebald, to jet black, 

 with a shining green lustre. In its nearly pure white winter dress, the 

 name of black guillemot is an evident misnomer, and that of doveky 

 or Greenland dove is much more applicable. It is remarkable that at 

 such seasons birds should be found both in complete summer and perfect 

 winter plumage. I should imagine that the former had been wintering 

 in the south and had never assumed the winter garb. In intensely 

 severe weather, in the depth of winter, the most purely white speci- 

 mens are to be procured. They breed on all the smaller uninhabited 

 islands, in holes under the rocks very little above the water-mark, 

 whence I have often extracted the little black downy young ones, and 

 have reared them on small fry, for which they are very clamorous, 

 uttering a querulous, impatient cry, unlike the adults, which are mute. 

 When fledged, the young are dingy black above and dirty white 

 underneath ; the white speculum on the wing is clouded with black 

 specks ; and the legs, which in the old birds are a vivid coral red, are 

 a dull reddish brown. The black guillemot is comparatively rarely 

 seen to fly, but dives boldly in the wildest broken water. It is better 

 eating than the common guillemot. 



Among the isles it is known as the carlag, which means a tuft of 

 wool, a descriptive name when in its winter plumage. Caileag, as it 

 is sometimes pronounced, would signify a tame, good-tempered little 



