THE BIRDS OF HELIGOLAND 



thick heel-joint, as well as the preponderance of yellow in their 

 plumage, are unmistakable signs of their youth ; in some of them, 

 indeed, the tips of the feathers of the back of the head still have 

 adhering to them the small appendages of the downy nestling 

 plumage. None of these flights of young birds are accompanied 

 by old individuals. Old Golden Plovers do not arrive until October, 

 and even then not very numerously, for most of them tarry in the 

 north or east until they are driven off by the advent of wintry 

 weather. At such times, however, they fly across the island in 

 thousands during dark December nights, without halting on their 

 journey. 



The Blackbird, again, is another species in the case of which 

 the time of migration in respect to age and sex can be determined 

 with the utmost exactness by reason of the difference between their 

 early and adult plumages. The young reddish-brown birds, with 

 which the migration commences, rarely make their appearance 

 before the middle of October; the old black males defer their 

 arrival until November, and of these latter, again, the last to arrive, 

 some weeks later, are the beautiful glossy black individuals with 

 orange-yellow bills. 



Hundreds of similar instances might be brought forward, all of 

 which will be discussed in their place under the headings of the 

 respective species to which they refer. We cannot, however, omit 

 to mention one other instance relating to a species the home of 

 which is somewhat farther removed from Heligoland than those of 

 the species already discussed. We refer to Richard's Pipit, from far- 

 distant Daiiria. Under very favourable conditions of weather, I 

 have, on several occasions, met with young birds of this species 

 almost entirely in their young light-bordered plumage, as early 

 as the end of August. September and October are, however, the 

 proper migration-months of these young birds, in the course of 

 which the early dress is gradually replaced by the olivaceous brown 

 early- winter plumage. Old birds in beautiful rust-coloured plumage 

 never appear here before the end of October, continuing during 

 the first half of November. The number of such individuals in the 

 course of the autumn migration is, however, invariably a very 

 limited one. The rule just established in reference to the order of 

 migration does not include certain solitary exceptions. These 

 however in the present case by no means discharge the important 

 function which it is sought to attach to them, viz. the leadership 

 of the young birds during their migration flights. To such excep- 

 tions belong the few old Starlings previously mentioned, which are 

 seen here almost every summer some two or three weeks before 

 the arrival of the flocks of thousands of young birds. The pro- 



