226 
stance, similar to that used by the other species, 
which renders the nest very hard and firm when 
the cement is dry. The eggs, which are white, 
and four or five in number, are very long in pro- 
portion to their breadth. 
TEEN, ARG DIC. 
STERNA ARCTICA, T'emm. 
The Arctic Tern, which even on the wing may 
easily be distinguished from the Common ‘Tern, 
both by its ery, which is shriller, and by its tail, 
which is more elongated, is precisely similar in 
its habits to that species, and frequently occurs 
intermingled with it. In the northern and western 
Islands of Scotland, on many parts of the coast 
of the mainland, and in the Frith of Forth, as 
well as in various parts of England, it is common. 
The eggs, of which there are generally three or 
four, are deposited in sandy or rocky places. 
They vary greatly in colour, being sometimes of 
a greyish yellow, and frequently of an olivaceous 
or brownish hue, with black and purplish grey 
blotches. 
