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COMMON TERN. 
STERNA HirunpDo, Linn. 
PLATE CCCIX. Anbutr. 
AurHoucn the Prince of Musicnano has thought that the bird 
named the Common Tern in America, differs from that bearing the 
same name in Europe, and has in consequence changed its appellation 
to that of Wilson’s Tern, I am of opinion that no difference exists 
between the Common Terns of the two Continents. The cry of both 
is besides precisely similar, so that with me there is no doubt what- 
ever as to their identity. Experience has shewn me that the mark- 
ings or white spots on the primary quills of Gulls, at one time assumed 
as a criterion by which species might be distinguished, cannot in the 
least be depended on, varying, as they always do, in individuals of 
the same species, at almost each successive moult. Then why, Reader, 
should not Terns exhibit analogous changes? The fact is, they do so; 
and it is almost impossible, on closely inspecting a dozen or more 
specimens procured at the same period, in either country, to find two 
individuals exactly corresponding in every particular. Some have the 
bill almost entirely black, while others have it more or less red and 
black, and tipped with yellow. The length of the tail-feathers, that of 
the tarsus, and the size of the inter-digital membranes, are all found 
to differ in some degree, if minutely compared. If species are to be 
founded on such slight differences, an ample field is open to those 
who are ambitious of being discoverers. At all events, I cannot help 
remarking here, that it seems to me improper to impose new names 
on objects, until it is proved by undeniable facts that they present 
permanent differences. 
I have observed this species along the Atlantic coast of North 
America, from Galveston Island in Texas to the Straits of Belle Isle 
on the coast of Labrador, both in spring and in early autumn. But 
when on the islands in Galveston Bay, in the month of April, I saw 
only a few arriving there from the west ; whereas, in the beginning of 
May great numbers arrived there from the east, settled at once, and 
commenced breeding. I felt eonvinced that the numbers which came 
— ae 
