XIV MIGRATION 363 
are most necessary, in order to keep the troop 
together, or, possibly, in clear weather the flight may 
be at too high a level for us to hear them. Around 
lighthouses, sometimes over inland towns, there is a 
perfect babel of sounds, among which a practised 
ornithologist can generally distinguish the notes of 
particular species. Superstition sometimes finds in 
the cry of the Wild Goose an omen of death. 
Order of Departure. 
In autumn the young birds, of many species at any 
rate, start first; then after an interval, sometimes 
extending to a month or two, follow the old birds, and 
after them some irregular flights, probably consisting 
mainly of cripples and young birds hatched late. 
Swallows often pass Heligoland in November, and in 
England stray specimens may be seen as late as that. 
About the same time as the great flights of young 
birds, often a little before them, there come to 
Heligoland a few old ones, still generally in their 
wedding plumage, which looks a trifle worn. These 
old birds, it is believed, are those who have not found 
mates and who, having no family ties to detain them, 
hurry to their winter homes. Every autumn there 
arrive there some Golden Plover (representatives of 
the bachelor birds just mentioned) still wearing the 
black breast plumage that is donned in spring ; then, 
more than a month after, come flocks of young 
birds. The same order of departure is observed 
among Starlings. The young birds begin to arrive in 
Heligoland in the latter half of June, the old birds 
