158 THE BIRDS OF IONA AND MULL. 



weather was so stormy and wet all the time they stayed that I 

 could not procure a specimen. They frequently cried to one 

 another when they became separated after a long submarine pro- 

 menade. Their cry consists of a sharp, grating, rapidly repeated 

 shriek. They were off and on during the third week in April. 



The Cuckoo brought his long overdue promissory note of 

 coming spring on the 2nd May ; and the Terns or Sea Swallows, 

 who also serve the purpose of marine Cuckoos on the rocky, 

 treeless coast of the Hebrides, filled the air with their shrilly voices 

 on the 12th May, which is three days earlier than they are due 

 at lona. 



Eight days ago I saw a Great Northern Diver in the loch. I 

 watched him for a long time with the glass. He was in full 

 summer plumage. The water being as smooth as glass, I had an 

 opportunity of remarking the characteristic styles of diving dis- 

 tinguishing various members of the genus " Dookers." The Great 

 Northern Diver bends his head gently back, then easily and 

 majestically bows it down under water, without the least sign of 

 hurry or effort ; the front portion of his huge bulk subsides gently 

 under the surface like a noble ship settling down by the head ; 

 as the tail end disappears after it, two splashes of water are dashed 

 up in the air by an upward stroke of the broad paddles, as the 

 noble bird precipitates himself into the middle depths. The 

 whole process is conducted with the deliberation to be expected 

 from a bird occupying the respectable post of Mhara Bhuachaille, 

 or herdsman of the deep, the fanciful name given him by the 

 Highlanders ; though, being a bird of easy temper, it does not 

 appear that he really uses his powerful bill and portly bulk to 



