THE BIRDS OF HELIGOLAND 243 



which only differs from T. alicke by its somewhat deeper buff 

 (rostgelb) coloration, shares with the latter form the tendency for 

 migrating westwards, and in virtue of this tendency reaches Europe 

 by way of Asia. 



In the coloration of all its upper parts, tail, and wings, this 

 small and handsome Thrush exactly resembles a Song Thrush. Its 

 lower parts are dingy white, with a tinge of buff colour on the neck 

 and upper breast. The sides of the neck and upper breast have 

 the spotted markings characteristic of all the Thrush species 

 Towards the upper breast, however, these markings, which at first 

 have the form of acute triangles, rapidly widen out ; nor are they as 

 black or as sharply defined as in the Song Thrush ; and at the sides 

 of the breast they pass into broad, dingy grey and very faint spots, 

 so as to be scarcely distinguishable from the grey-clouded flanks. 

 The middle of the breast, the belly, and under tail-coverts are 

 of a uniform white. 



The measurements of the bird killed here were as follows : — 

 total length, 6'34 ins. (161 mm.); length of wing in repose, 3-74 

 ins. (95 m.rii.) ; length of tail, 2-64 ins. (67 vim.) ; length of tail 

 uncovered by wings, 106 in. (27 mm.); length of beak from 

 forehead to point, "43 in. (11 mm.); length of tarsus, 110 in. 

 (28 mm.). 



The breeding range of this species extends across Canada and 

 Alaska as far as the Arctic Circle. The paler, more grey-coloured 

 individuals, which are said to predominate in the eastern portions 

 of their breeding home, whence, accordmg to Seebohm (Cat. of 

 Birds of Brit. Mus., v. 202), they pass over to Kamtschatka, have 

 been separated from the more vividl}' rust-yellow examples under 

 the name T. alicice. How far this separation is correct cannot 

 be decided here. We would only remark that the example which 

 was met with in Heligoland is of a fairly vivid buff (rost- 

 gelb) colour. 



A clutch of eggs of this species, of the genuineness of which 

 no doubt can exist — inasmuch as I received it from the Smith- 

 sonian Institution at Washington — in the ground colour and 

 colour of the markings almost exactly resembles diffusely-marked 

 examples of the Ring Ousel, though the ground colour may be 

 somewhat of a less rich sea-green and the colour of the markings 

 not quite so brightly ferruginous (rostroth) as in the latter species ; 

 moreover, a few violet-grey (violettgraue) blotches occur between 

 these markings. In two of these eggs the markings are spread over 

 the whole surface, being somewhat denser at the thicker end of 

 the eg^. In another the markings are collected in a zone. In the 

 fourth the violet-grey (violettgraue) blotches are more numerous, 



