THE BIEDS OF HELIGOLAND 251 



the same age ; moreover, in T. ruficollis, the shafts of the tail- 

 feathers are whitish rust coloured, which is not the case in T. 

 atrigularis. 



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

 in both species pure white ; whilst, however, in T. ruficollis, the 

 longest of the latter feathers are only slightly tinged towards their 

 roots with olivaceous grey (olivengrau), they are, in T. atrigularis, 

 almost entirely olivaceous greyish brown (olivengraubraun), which 

 colour also persists over a large part of the next pair of feathers. 



Dresser says that the nest of this species has not yet been dis- 

 covered ; but it must breed far up in northern Asia, since it has 

 been met with on migration from the Obi to the sea of Ochotsk. 

 In the case of the first-named river, we have only one record of its 

 discovery, viz. that of Finch ; but Prjewalsky notes it for north 

 Mongolia as the most numerous of all the Thrushes which pass 

 through that district ; while Swinhoe met with migrants of this 

 species in Northern China. One might therefore expect to dis- 

 cover its nesting places chiefly in the Lena district, especially since 

 Seebohin does not appear to have met with this species among the 

 rich store of Thrushes taken by him at the Jenesei. 



I have in my possession an egg alleged to belong to this Thrush, 

 which I received in 1874 from Taczanowsky. It resembles a small, 

 very finely and densely spotted egg of T. torquatus, and is T14 in. 

 (29 mm.) long, and -82 in. (21 mm.) broad. 



75. Black-throated Thrush [SCHWAEZKEHLIGE DROSSEL]. 

 TURDUS ATRIGULARIS, Ternminck. 



Turdus Bechsteinii. Naumann, ii. 310 ; T. atrigularis, xiii. 330. 



Black-throated Thrush. Dresser, ii. 83. 



Merle a gorge noire. Temminck, Manuel, i. 169, iii. 93. 



Though my collection is graced by the presence of many rare 

 and beautiful Thrushes, I have just cause for bitter regret at seeing 

 the place of the present species still unoccupied. The bird has been 

 killed, so to speak, all around this island, in England, Belgium, 

 Denmark, Sweden, East Prussia, Mecklenburg, and Oldenburg, 

 whilst from twenty to thirty instances of its occurrence are recorded 

 from Central Europe. Heligoland, however, has up to the present 

 not been recorded as a locality. On one occasion, it is true, a 

 beautiful old male was seen late in May in the immediate neigh- 

 bourhood of the island so near, in fact, that the yellow basal por- 

 tion of its bill could be recognised quite distinctly. Unfortunately 

 the general migration was already at an end, no gun was at hand, 



