200 
GREBES. 
tertials large and quadrangular, but becoming small 
and nearly round upon the lower part of the back 
and rump. Flanks and sides black spotted with 
white, the rest of the under plumage wliite ; the 
long axillary feathers the same, with a black stripe 
down their centres ; tail short and rounded, consist- 
ing of twenty feathers ; legs greyish black, paler on 
the inside.” 
The other British form among the Colymbidao is 
that of the Grebes, also peculiarly aquatic and to- 
tally unfitted for a life upon dry land. If we take 
the last form as typical of this family, we shall find 
some varieties in the structure of the Grebes, al- 
though they are even more expert divers. The tail is 
almost wanting and the toes are unconnected, but 
are widely lobed. The plumage is very close, and 
is silky to appearance, during the breeding season 
changing to deep brown and chestnut, and receiving 
