99 



When we read of this species passing Heligoland in large 

 numbers, including a few adult males, as late as May 26th, and 

 which are said to be en route to a district in the most southern 

 locality of its breeding range, shall we not be justified in assum- 

 ing rather that flocks travelling so late are migrants to districts 

 in the far north of Scandinavia? As has been before pointed 

 out, Messrs. Seebohm and Harvie Brown record the arrival of the 

 Bluethroat in the Petchora Valley — many hundred miles further 

 north — on the 22nd of this month, by which time, no doubt, the 

 Bluethroats in the Dovre Fjeld' will have commenced breeding 

 operations. Moreover, the numbers in which, under favourable 

 conditions, the species is observed, and the duration of its 

 .migrations, i.e., end of April to end of May, also point to the fact 

 that the Bluethroats passing Heligoland are travelling to many 

 different localities in Norway and Lapland. How can we, there- 

 fore, accept the statement that it is the westernmost extremity of 

 a broad advancing migratory column alone which touches the 

 island ? Would it not bo more reasonable to assume that the 

 Bluethroats migrating to Northern Europe from their winter 

 quarters in Egypt are travelling in many narrow streams, and 

 that the fact of their non-observance in intermediate countries to 

 the south of Heligoland is partially owing to this mode of flight ? 

 In connection with the latter point, the evidence of other 

 authorities quoted by Herr Gatke (p. 265) are interesting, and 

 point to the possibility that with an increased number of observers 

 the Bluethroat might be found regularly occurring in many inter- 

 vening districts. He remarks : " Eespecting Northern Germany, 

 Sylvia suecica has, according to recent statements, not only 

 been met with in isolated instances ; but surprising as it may 

 appear, has actually remained to breed near Waren, in Mecklen- 

 burg, and near Emden in Friesland." 



As additional evidence in favour of the unbroken character 

 of the flight of the Bluethroat, the fact of its never having been 

 observed at the lantern of the lighthouse is cited by Herr Gatke. 

 But what does this prove ? Might not flocks which had broken 

 their journey in some previous locality pass over the island at 

 a considerable height ? If this should occur they would not be 

 likely to be attracted by the glare of the light. 



