During the heat of the day many of them disperse up and down throughout the corn, pasture, or fallow fields, in search of food.—These they beat with great diligence, traversing them again and again at the height of about ten feet, as before. When any suitable object meets their eye, they immediately round to, alight on the ground, and, generally keeping their wings extended upwards, at an acute angle with their bodies, seize it.
The black-headed gull is a lively, graceful bird, and has, like its congeners, a very elegant and buoyant mode of flight. A peculiarity in its habits, which I have not seen noticed, is, that it is very crepuscular. I have repeatedly seen numbers of them flying about long after sun-set; and lately I have remarked that they come abroad in the evening, apparently for the purpose of catching insects, which they do on the wing, after the manner of the swallow tribe. On the 22nd of this month, I watched the proceedings of a number of these birds by the banks of the Jed, between 9 and 10 o'clock. There was a small grove of trees at a short distance from the river, to which some of them resorted, flying from one extremity to the other, and returning again, all the while seemingly engaged in the pursuit of insects of some kind. Their motions were much the same as those of swallows, although somewhat slower; they sometimes remained hovering and suspended while catching an insect, so long and so near the trees that T thought they were going to alight. Others of them scoured the fields and the water-side, and others again followed the course of the river, but all apparently intent on the capture of some winged prey. It was very curious to observe these gulls hawking about exactly like the Hirundines. In Yarrel's 'British Birds' it is mentioned that the Rev. Mr. Lubbock had seen the brown-headed gull engaged in catching cockchafers; whether the insects in this case were cockchafers, I am unable to say. Archibald Jerdon.
Boujedward, June, 1843.
Note on the Nests of Martins on Sand-stone Rocks. Many nests of martins (Hirundo urbica) are built on some of the precipitous rocks of sand-stone, which, in various places, over-hang the river White-adder, flowing through Berwickshire into the Tweed. They are placed wherever a projecting ledge gives them shelter from above. In one place, hist autumn, I counted from thirty to thirty- five, at a height of perhaps forty-
