162 BRITISH SEA BIRDS. 
nuptial dress. In this plumage the throat is marked 
with an elongated patch of chestnut ; the head, and 
sides of the neck are ash-brown, the latter striped 
with black and white, the general colour of the 
upper plumage blackish-brown, sparingly spotted 
with white, and the under parts are white. The 
plumage, as in all the Divers, is remarkably dense 
and compact, adapted in every way to the aquatic 
habits of the bird. The Red-throated Diver is 
a fairly frequent visitor, during autumn and winter, 
off the English coasts, often entering bays and 
the mouths of wide rivers. In summer, however, 
it becomes much more local, retiring then to haunts 
in Scotland, especially in the Hebrides and along 
the wild and little populated western districts, from 
the Clyde northwards to the Shetlands. Outside 
our limits, this Diver has a very wide distribution, 
occupying in summer the Arctic and north temperate 
regions of Europe, Asia, and America; in winter 
migrating southwards for a thousand miles or more. 
The Red-throated Diver is certainly the most gre- 
garious species, and in winter may not unfrequently 
be seen in gatherings of varying size. In connection 
with this trait, mention may be made of the extra- 
ordinary numbers of this bird that, on the 2nd and 
3rd of December 1879, passed Heligoland. The 
movement was not strictly a migratory one, but 
a grand flight of storm-driven, frozen-out birds, 
seeking more congenial haunts. Géatke tells us 
that during this visitation, there was about thirteen 
