116 THE BIRDS OF HELIGOLAND 



1875. Sept. 17. Emberiza pusilla; Anthus cervinus and S. superciliosa. 

 Two examples of latter species. 



1879. May 26. Fako eleonorce and Alauda pispoletta. Both new to 



Heligoland and Germany. 



Sept. 27. E. pusilla, two ; E. rustica, one ; and E. aureola. 

 ,, 28. E. pusilla and E. rustica. 



Oct. 8. S. reguloides, E. rustica, two to three examples ; 



E. pusilla; Anthus cervinus and Alauda alpestris, 



the latter in flocks of hundreds. 

 10. E. rustica and pusilla. 



14. S. superciliosa, two examples. 



1880. June 23. Saxicola deserti and Papilio podalirius. 



Sept. 26. Sylvia superciliosa, E. pusilla, and Musdcapa parva. 



30. E. pusilla, Sylvia tristis, and S. superciliosa. 



Oct. 10. Turdits fuscatus. A day afterwards, E. pusilla. 



I must further make special mention of the 1st of October 

 1869, on which day there occurred on the island the Little Bunt- 

 ing, Red-throated Pipit (Anthus cervinus), two examples; the 

 Red-breasted Flycatcher, three examples ; White's Thrush and 

 Yellow-browed Warbler. 



On the day following I obtained Turdus swainsoni, which latter 

 likewise no doubt reached this island by an east-to-west route of 

 migration. The occurrences enumerated above were almost always 

 accompanied by larger or smaller numbers of Richard's Pipit. 



In the enumeration of these birds mention has also been made 

 of a butterfly, Papilio podalirius. This insect, as is well known, 

 only in rare cases advances beyond northern Germany, and on this 

 island also had been seen on only one previous occasion. There 

 can therefore be no doubt that the same atmospheric conditions 

 which favoured the journey hither of the Desert Chat from the 

 south, in company with which it arrived on the same day, also 

 induced this lighter-winged stranger to wander across the sea. 

 That Lepidoptera during their more extended flights are subject to 

 the same meteorological influences as birds I have been convinced 

 by the experience of many nights in July, during which I have 

 caught numerous nocturnal Lepidoptera not belonging to our insect- 

 fauna, the weather of these nights being invariably such that, if it 

 had occurred a few weeks later, it would have conducted hither 

 innumerable Wheatears. It has, in fact, occurred repeatedly that 

 Lepidoptera, especially night-flying species, have passed over this 

 island in countless swarms at the time of powerful bird-migrations. 

 Thus, during the night of the 25th of October 1872, thousands of 

 Hybernia defoliaria, mixed with smaller numbers of H. auran- 

 tiaria, passed over the island in the company of large numbers of 



