734 THE BIRDS OF YORKSHIRE. 



occasionally two are seen together, as on 4th December 1877, 

 at West Scar Head, Redcar ; again on i6th March 1892, I 

 watched through a telescope a couple feeding near the shore ; 

 and in November 1893 two were near my boat inside the Redcar 

 rocks. The marvellous rapidity with which this bird can 

 swim and dive under water has frequently been commented 

 upon ; I have known one remain under the surface, after 

 diving, and not re-appear until it had traversed a distance 

 of at least half a mile, whilst in swimming it can easily out- 

 distance a pair-oared boat. A specimen that I had alive for 

 some time, when placed in the water, gave utterance to a 

 mournful, not unmusical, cry. 



The average weight of a Northern Diver is stated to be 

 between nine and ten pounds ; the heaviest I have note of is 

 a female example, obtained at the Teesmouth in November 

 1886, which weighed twelve pounds. 



Local names : Loon or Leaan, in general use r Herring 

 Loon on the Humber ; Big Northern Diver at Redcar ; 

 and Penwings is an old Redcar name, probably a corruption 

 of Penguin. 



WHITE-BILLED NORTHERN DIVER. 

 Colymbus adamsi (G. R. Gray). 



Accidental visitant from northern America. 



The only claim of this bird to be admitted to the Yorkshire 

 list rests on the occurrence of an example recorded by the 

 late J. Cordeaux ("Birds of the Humber District," 1899, 

 p. 38), as having been obtained in January 1897, at Filey, 

 which came into the possession of the late D. Brown of 

 that place. I have been unable, however, to obtain any 

 further information regarding this specimen. 



