NATURAL HISTORY SOCIETY OF GLASGOW. 125 



different, being most plentiful where the Black-throated Diver is 

 scarcest, and vice versa. It frequents more retired and out of-the- 

 way spots than the BLack-throated Diver, and often breeds at a 

 much higher elevation. It also differs somewhat in its nesting 

 habits, preferring the shore of a small peaty tarn to the islands of 

 a larger loch. The eggs are considerably smaller ; and on comparing 

 a small series with a larger one of the eggs of the other species, 

 they are found to vary more, both in the ground colour and in the 

 markings. 



The cry of the Eed-throated Diver is perhaps one of the most 

 extraordinary and startling sounds a person can well listen to, 

 especially when heard for the first time. On one occasion a friend 

 and myself were rowing on Loch Assynt, when the wild, half cat- 

 like, hiilf infant-scream-like cry came loudly and distinctly across 

 the water. We were both startled, not even excepting our steady 

 old highland boatman, who had often heard it before ; whilst my 

 friend, who had never heard it until that occasion, could hardly 

 be convinced that it was not a cry of distress from some drowning 

 person. So human-like was the strange shriek, that even after 

 we had seen the birds we could hardly divest ourselves of a dis- 

 agreeable feeling that it might have been a child drowning after all. 



Ohs. G-reat Northern Diver, Colymbus glacialis (Linnaeus). — Mr 

 Selby records that "A single pair was seen in the Bay of 

 Balnakill, mouth of the Durness Firth, both adult birds, and in 

 full adult plumage." He suggests that " It is probable that they 

 had their nest upon one of the numerous islets that abound in the 

 bay." Sir William Milner also observed the species; and there 

 are numerous other records of these birds having been seen late 

 in summer on various parts of our coasts. 



On June 5th, 1868, I identified a pair of these birds upon a wild 

 inland loch in Sutherland, and soon afterwards sent an account of 

 my discovery to a natural history periodical (" Zoologist," 2nd 

 series, p. 1309). I am quite positive as to the correctness of 

 my observation, and, from various scraps of information that have 

 since reached me, I am also decidedly of opinion that the Great 

 Northern Diver has bred in Sutherland. 



Mr Dunbar reports that he saw Great Northern Divers, with 

 " one young one," on Loch Endorb, where there were also at the 

 same time two or three pairs of the Black-throated Diver ; " so 

 that the two species were easily distinguished by the great disparity 



