416 NATATORES. COLYMBUS. DIVER. 



of a plain oil-green, to which TEMMINCK, in his account, 

 adds a few brown spots. It is, therefore, probable, that they 

 are subject to some variation, from an immaculate to a spot- 

 ted appearance. When fairly on wing, the Red-throated 

 Diver flies with great strength and swiftness, and often at a 

 considerable height ; but, except to descend from the lakes 

 to the sea, or to perform its migrations, it seldom thus exerts 

 its pinions, trusting, in avoidance of danger, more to its 

 powers in diving ; and this it performs with as much ease as 

 its congeners, remaining nearly as long submerged. MON- 

 TAGU, in the Supplement to his Ornithological Dictionary, 

 under the article Speckled Diver (the young of this species), 

 says that the distance between the place of immersion and 

 emersion, in a bird which he pursued upon a canal, averaged 

 from eighty to ninety yards ; and that the rate of progress 

 beneath the surface was between six and seven miles in the 

 hour, whilst by swimming it did not exceed four and a-half. 

 This species utters at times loud cries, and also hoarse croak- 

 ings, which, having been observed by the natives to precede 

 foul weather, have obtained for it the name of the Rain Goose 

 in the Orkneys, where all the larger sea-fowl receive the ap- 

 pellation of Goose, and the smaller ones that of Duck*. 



General PLATE 78*. represents the Adult Bird, killed in the spring. 



tion. nP Bill blackish-grey, two inches and two-eighths in length 

 Adult bird. from the forehead to the tip ; the upper mandible strait, 

 the lower one with a long ascending angle, giving to the 

 bill the appearance of being slightly recurved ; tomia 

 of both mandibles much inflected and very sharp. Sides 

 of the head, chin, and sides of the neck deep smoke- 

 grey. Crown of the head blackish-grey ; the feathers 

 being margined with smoke-grey. Nape and hind part 

 of the neck glossy blackish-grey, margined with white. 



* Sir WILLIAM JARDINE had a specimen of the Roller sent to him from 

 Shetland, where it was killed, as a rare and curious Duck. 



