* 
DIVERS, GREBES, AND CORMORANTS. 165 
and functionless tail, and dense compact plumage 
of a peculiar silky texture. The twenty or so 
species of Grebes are grouped into a single family, 
called Podicipedide, of which the genus Podzceps 
(or more correctly Podzczfes) contains the greater 
number. The Grebes are almost cosmopolitan. 
Five well-marked species are found in Europe, all 
of which, being visitants or regular residents, are 
included in the British avifauna. In the. colours 
of their plumage the Grebes are not very remark- 
able, with the exception of the crests or tippets 
assumed by some species during the nuptial period : 
plain browns predominate on the upper surface ; 
the underparts are almost always glossy white. 
The Grebes fly well; dive with great dexterity, but 
their movements on the ground are not graceful. 
The young are hatched covered with close down, 
and able to swim at once. The Grebes have a 
complete moult in autumn, and assume their nuptial 
ornaments in spring. The quill feathers are moulted 
so rapidly that for some little time the birds are 
unable to fly, as is the case with the Geese and 
some others. 
It is only during the winter months that 
the Grebes become pelagic or marine in their 
habits, and even some species are much _ less 
addicted to a sea life than others. We will 
now proceed briefly to glance at the British 
species. 
