THE BIRDS OF HELIGOLAND 399 



duals during the summer months at all events seems to admit of 

 the conclusion that these birds may have been bred in the neigh- 

 bourhood of the island, perhaps in Sleswick-Holstein. I do not, 

 however, share the view that breeding attempts of this kind, made 

 in districts far distant from the regular home, justify one in assum- 

 ing an extension of the breeding area; for, under the conditions 

 discussed in the chapter on ' Exceptional Migration Phenomena ' 

 (Part I.), it is quite possible that a male and female, happening to 

 meet far beyond the normal limits of their breeding area, may pair 

 and breed without either parents or offspring ever returning to the 

 same place afterwards. 



Thus, during the wonderful irruption of Pallas' Sand Grouse in 

 1863, some of these birds were found breeding as far west as Den- 

 mark ; but in the autumn both the young and old birds departed, 

 never to return. The same phenomenon was repeated in 18S8. 



The first example of this species which I obtained here was an 

 old male, shot on the 14th of July 18G0. I next secured a remark- 

 ably beautiful male bird on the 8th of June 1879. On the 28th of 

 the same month five young grey birds were seen, only one of which 

 displayed a very faint tinge of yellow ; and on the 1 1 th of July of 

 the same year, another old bird was seen, but was not shot. 



The summer in question was exceptionally rich in occurrences 

 from the far South-east. Thus, May brought us AlavAa pispoletta, 

 Falco eleonorce, and Sylvia viridanus ; June, Sturnus roseus and 

 Emberiza melanocephala, on two occasions in each case ; while 

 Hiniantojrus rufipes, as well as another example of S. roseus, were 

 seen in July. Among so numerous a stream of migrants proceed- 

 ing from the south-east — as from the instances cited we may 

 assume to have advanced over the whole of Germany — a pair 

 of Serin Finches may very easily have come together, and, like 

 Pallas' Sand Grouse m the above instance, have bred far from 

 their home in Sleswick-Holstein or Denmark, without an excep- 

 tional case of this kind having of necessity any influence on the 

 distribution of the species. In Heligoland the bird has not been 

 seen again since that time. 



The breeding stations of this species extend through southern 

 Europe from Portugal to Greece. In the north it is found breed- 

 ing in still fau'ly large numbers as far as Frankfort-on-the-Main. 



