Terns, on the other band, pass through the air with a more bounding motion, turning to the right on to the left
and dipping perpendicularly towards a Dragonfly or any other insect that may have attracted their attention.
Their aerial actions have been compared to the hawking of the Nightjar ; and I may add that they are not
unlike those of the Great Bat (Vespertilio noctula).

«The evolutions of the Black Tern are so rapid, and its turns so short,” says Montagu, “that by this means
it sometimes escapes the talons of predacious birds, as we had once an opportunity of witnessing. In a
very hard gale of wind many ‘Terns were sporting over the water, when a Peregrine Falcon passed like a shot,
singled out his bird, and presently coming up with the chace, made a pounce ; but the great dexterity of the
Tern avoided the deadly stroke, and took a new direction. The Falcon by his superior velocity, soon regained
sufficient elevation to successively repeat his pounces, but at last relinquished the pursuit.”

Scotch writers state that the Black Tern is not common in that northern country ; and those who have
written on the Birds of Ireland, that it is an occasional visitor only, chiefly in autumn, and in an immature
state.

Mr. Rodd, when speaking of its occurrence in the extreme west of England, informs us that it is “generally
observed in the autumnal months, and nearly every year, in more or less numbers, both on the sea-side and
inland. In its full black plumage it is rarely met with in Cornwall.”

Temminck, in his ‘ Manuel d’Ornithologie,’ says :—

‘« Habite: les riviéres et les bords des lacs d’eaux douces, mais particuliérement des marais ; trés-accident-
ellement sur les cOtes maritimes; assez abondant dans le nord, jusques au cercle arctique; trés-nombreux
en Hollande et dans les grands marais de la Hongrie. Vit en grandes troupes dans les marais de Tombole
et d’Ostia, mais n’y vient pas avant les premiers jours d’avril.

‘‘Nourriture : insectes ailés et vers aquatiques.

“Propagation: niche en grandes bandes dans les marais, parmi les roseaux clair-semés et sur les grandes
feuilles de nénuphar qui flottent sur les eaux; pond depuis deux jusqu’a quatre ceufs, d’un olivatre clair
marqué de nombreuses taches brunes et noires, dont la réunion forme un large cercle sur le milieu de l’ceuf.”

The late Captain Loche states that it frequents the three provinces of Algeria,

Besides inhabiting all the temperate parts of Europe, North Africa, Madeira, Asia Minor, and Persia
(according to Mr. Jerdon), it must be added to the Indian list, Mr. Blyth having seen Indian examples collected
by Dr. L. Stewart. I believe it is also found throughout the whole of North America. Dr. Elliott Coues, in
his valuable review of the Terns of that country, says :—*‘‘I have critically compared quite a series of European
and American specimens in all stages of plumage, but have been entirely unable to detect the slightest
discrepancies between the birds of the two continents. The specimens before me are all absolutely identical
in size and relative proportions of different parts ; and the colours of those of the same age correspond minutely.
There do not appear to exist the slightest characters upon which to base specific distinction.”

A nest of four recent eggs, that came into my possession before being blown, were of a pure olive, profusely
marked with large blotches of dark rich umber, most numerous and forming a distinct though somewhat
irregular zone towards the larger end; they varied a little in size, three being an eighth of an inch longer
than the fourth, and two being a sixteenth wider than the others, the largest being one inch and three-eighths
in length, by one inch and a sixteenth in breadth.

There is little or no difference in the size and colouring of the sexes. The adults in summer have the bill
black, the inside of the mouth flesh-colour ; the irides dark brown; the tarsi, toes, and webs dull red; nails
black ; head, neck, breast, and belly dark or blackish lead-colour ; back, wings, and tail slate-grey ; vent
and under tail-coverts white.

The Plate represents an adult male and female, of the natural size, and a young bird in the dress of its
first autumn, about a third less.