On Mountain and Loch. 103 



islands again we may meet with colonies of Arctic 

 Terns. These graceful birds are quite a summer 

 feature of the lochs, their airy movements as they 

 fish just off the shore being highly interesting. The 

 Common Tern is much more local, and yet there are 

 not a few colonies scattered up and down these lochs 

 amongst the Hebrides, at least as far north as Skye. 

 Of the Terns we shall have more to say in a later 

 chapter (conf. p. 22 1). Where the cliffs are steep by the 

 loch-side, in not a few of these northern waters, we 

 shall be sure to find the Black Guillemot, a bird, as 

 its name' indicates, almost uniform black in colour 

 (during summer), with white wing-bars and coral-red 

 legs and bill. This bird is never seen in such num- 

 bers together as the better-known and larger Common 

 Guillemot; rather is it found in scattered pairs, fish- 

 ing close inshore where the rocks fall sheer down 

 into deep water. Its habits, however, are very 

 similar; it dives with the same agility, feeds on 

 fry, crustaceans, and small shell-fish, and is just as 

 thoroughly marine in its tastes. We must note, 

 however, one important difference, and that con- 

 cerning its nesting economy. Like the Razor-bill, 

 it breeds in holes and fissures of the rocks, makes 

 no nest, and its eggs are very similar to those of the 

 latter species but much smaller, and two in number. 

 As most readers may be aware, the Guillemot and 

 the Razor-bill are content to lay one only. Both 



