202 THE MIGRATION OF BIRDS 



on the Arctic circle in Siberia. The main line of 

 migration of this, as well as of several other species of 

 birds breeding in the same district, is eastwards, passing 

 through North China and conducting them to South 

 China, Burma, and the eastern portion of India, where 

 they winter in abundance. Several birds, some nearly- 

 allied, and one congeneric, migrate west instead of east 

 from the same breeding-grounds, and with these a few 

 yellow-browed warblers appear annually to mix and find 

 their way to Europe, passing Heligoland in small numbers 

 nearly every autumn. Probably most of these wanderers 

 perish during the winter, as they have been observed in 

 spring on Heligoland only once every few years. This 

 charming little bird has once been recorded from the 

 British Islands. I saw one or two during my short stay 

 on Heligoland, and was fortunate enough to shoot one. 

 For nearly a week, whilst I was visiting this interesting 

 locality, the weather was unfavourable. There were 

 scarcely half a dozen birds on the island. I used to take 

 a constitutional with my gun twice or thrice a day, spend- 

 ing most of the rest of the time in Mr. Gatke's studio, 

 chatting about his birds, visiting regularly Aeuckens, the 

 bird-stuiifer, to inquire if any one else had had better luck. 

 On the nth of October I shot three shore-larks. 

 Aeuckens told me that the appearance of this Arctic 

 species was a very good sign, that he had often noticed 

 that a few birds always preceded the favourable weather, 

 and that we might soon expect a change and plenty of 

 birds. The next day the west winds, which had pre- 

 vailed for a week, slackened a little. In the afternoon 

 it was a calm, with a rising barometer ; in the evening 

 a breeze was already springing up from the south-east. 

 I called upon Gatke, who advised me to go to bed, and 

 be up before sunrise in the morning, as in all probability 



