WATER BIRDS. 225 
_ The numbers that frequent Thoresby Lake vary con- 
siderably: in some years there have not been more than 
fifteen or twenty ; in others as many as thirty, or even 
forty, as in 1855. Welbeck Lake is generally visited by 
a small party, and sometimes Rufford also, and a few 
are annually seen on the Trent. 
There is always a large proportion of males in adult 
plumage in every flock, and it is a very pretty sight to 
see them chasing each other, diving in apparent play- 
fulness and emerging immediately ; when they are 
feeding they remain much longer under water, and 
often traverse a space of seventy or eighty yards before 
coming to the surface. J have had many opportunities 
of observing their habits from the thick plantation on 
the border of the lake already mentioned, where I could 
conceal myself close to the water without being per- 
ceived, and many an hour have I passed there in watch- 
ing their varied motions. They swim with their bodies 
low in the water, but yet with great activity and com- 
mand, and I have seen them submerge themselves until 
their backs were almost covered ; this is particularly the 
case with the female when making amorous advances to 
the male, her head and neck at the same time being 
outstretched and laid flat on the surface, until at a little 
distance she is almost invisible. Unaware of my vicinity, 
they often approached very near me, letting me inspect 
them closely. As the season drew on, the males gave 
some indications of choosing their partners ; two or three 
would select the same female, and pursue her most un- 
ceremoniously for some time, she all the while diving 
incessantly to elude the pursuit of her obnoxious suitors, 
or to aid that of the favoured one, reminding me often 
of the racing courtships of the Tartar maidens and their 
Q 
