426 The Outline of Science 



but, on the other hand, scarcely a minute elapsed without the 

 arrival of a fresh party of from half-a-dozen to a score of birds. 

 They seemed to fly low over the sea, but rose as they approached 

 to the level of the cliff-tops. We could not make them out at any 

 distance, for the observer can find no worse background for small 

 birds than grey, moving water. The stream was continuous and 

 the direction unvarying, so far as we could judge. Each party 

 rose to our level on the top of the north point, flew unhesitatingly 

 along the western side of the island, and disappeared again at the 

 south-western corner. Not one in a hundred quitted this line or 

 stopped to circle round; none seemed inclined to break their 

 journey so early in the day, in spite of the contrary elements. The 

 whole was for us just a momentary peep at one of the countless 

 tiny channels by which the bird-life of northern Europe was then 

 ebbing southward." 



Migration of Starlings 



A more comprehensive idea of migration is obtainable from 

 Gatke's observations extending over the whole length of a season; 

 let us summarise the diurnal movements of starlings, as observed 

 by him on Heligoland during the autumn of 1878. Early in June 

 came a few old birds in worn plumage, birds which had probably 

 remained unmated or had early lost their broods. On the 20th 

 June came the first great flights of young birds of the year, mi- 

 grating by themselves in advance of their parents although only 

 a few weeks out of the egg. These youngsters continued to pass 

 till the end of the month to the extent of thousands daily. In 

 early July the daily passage was estimated in tens of thousands, 

 and on the 25th the movement closed with the passage of "im- 

 mense multitudes." Two months followed during which no star- 

 lings, young or old, were to be seen. On the 22nd September old 

 birds, now in fresh plumage, passed in flights of many hundreds. 

 During October the flights increased to thousands, and on the 14th 

 the movement reached a climax with "starlings in hundreds of 



