COMMON TERN. 
88 
known to what countries this bird resorts for that pur¬ 
pose. The migratory journeys are often performed during 
the day, when the birds fly at a great height and appa¬ 
rently very slow. 
The flight of this species is generally quick when in 
pursuit of its prey, and its evolutions very greatly resem¬ 
ble those of the chimney swallow; it is consequently a 
beautiful and amusing sight to watch the bird when on 
the wing. It is frequently seen running about and pick¬ 
ing up insects, or sitting for rest on the shingle; its chief 
food consists of flsh, either dead or alive, which it catches 
for itself, or obtains by pursuing and harassing the smaller 
gulls, until they disgorge the fresh-caught fish, which the 
Tern catches up before it reaches the watery surface in its 
fall. During stormy weather, when the waves of the 
sea are high, the present species frequently flies up and 
down the course of rivers, where it finds food with more 
ease and certainty. 
On the 6th of October, 1846, we shot two terns as high 
up the Thames as Chertsey Weir; judging from the lateness 
of the season, they were probably on their migratory journey: 
one of them was an immature male of the Common Tern 
in autumn plumage; the other, a young of the year, of the 
arctic tern ; this is rather a remarkable circumstance, as the 
arctic tern is said never to be found inland. It afforded us, 
however, a good opportunity of comparing the two species 
together. 
That the Common Tern breeds in most of the before- 
enumerated northern countries of Europe is well authen¬ 
ticated, but where the greater numbers are produced, 
whether high northward, is not decided, particularly since the 
arctic tern has proved a distinct species. The chosen locality 
is invariably some extensive sandy or shingly flat, where 
