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observations upon them have reference, as might be supposed, to the dates of their arrival and departure, or, more correctly speaking, to the dates when they were first heard or seen and last observed. When referring some time previously to the utilization of such observations, it was remarked that upon various points some addition to our knowledge was desirable. Amongst other interesting facts, for example, might be ascertained the precise line of direction in which various species migrate, the causes which necessitate a divergence from this line, the relative proportions in which different species visit us, the causes which influence the abundance or scarcity of a species in particular localities, the result of too great a preponderance of one species over another, whether beneficial or otherwise to man as a cultivator of the soil, the simultaneity or otherwise of departure from this country in autumn, the causes operating to retard such departure, and so forth. All these are matters of interest, especially to those who reside in the country, and have leisure to inquire into the subject. Let us see how far the observations supplied furnish a reply to these inquiries.
Of the thirty species of migrants mentioned, the Swallow, as might be supposed, has attracted the largest share of attention, and in regard to the number of observations made upon it stands at the head of the list with forty-three. The Cuckoo comes next with thirty-eight; the Chiffchaff and Swift follow with thirty and thirty respectively; and so on through the list, as given below, to the Reed Warbler, upon which bird, strange to say, no more than three observations were made.
The following list will give some idea of the amount of attention which each bird received.
The first Swallow was seen, not as might be supposed in the south or south-east of England, but four miles south of Glasgow, on the 2nd of March, and Mr. Robert Gray states that this is the earliest record of its arrival in Scotland. It is, indeed, an exceptionally early
arrival, for nearly a month expired before another was seen at Cromer, on the 31st of the same month, and six weeks elapsed between the first and second appearance of the bird in Scotland. On the 1st April, with a S.E. wind, this harbinger of spring arrived at Great Cotes, in Lincolnshire, and on the 3rd of that month was noticed simultaneously at Nottingham and Taunton. From the 6th of April the arrival of Swallows was pretty general until the 13th, when they were first noticed in Ireland at Ballina, co
Mayo, and on the following day at Glasnevin, Dublin, and at Bray, in the county of Wicklow. The temperature then at Bray was 530, and the wind S.W. In these localities and dates there is nothing to indicate anything like a precise line of immigration; on the contrary, the birds first appeared where they were least expected. The prevalence of gales, however, at that particular season doubtless operated to retard their progress, and induced them to linger about sheltered localities where food could be obtained. Mr. Wm. Jeffery, who is well situated for observation on the Sussex coast, between the downs and the sea, remarked that most of the spring migrants were several days later than usual in their arrival, and the Swallow in particular not only came later, but lingered longer than is its wont in his neighbourhood. A single bird of this species was seen by him, flying round a steam threshing-machine, on the 10th of December. "Whether it had been disturbed," he says, "from hybernation in the oatrick which was being threshed, or only attracted by the warmth from the engine, I cannot say. It flew very weakly, and was not long seen."
On the 2nd of November, with the temperature at 45•5°, and the wind W., the species was still in the neighbourhood of Huddersfield, and on the 13th November, during cold weather, two were seen on the beach at Exmouth. I may here remark that but little attention is paid to the time of departure of a species compared to that which is given to the date of its arrival.
The Martin was observed to come later and go earlier than the Swallow, the earliest and latest dates being respectively April 10 at Marlborough, and November 7 at Leiston, Suffolk. And in the case of this bird the movement northwards might be traced by the dates, as Wiltshire, April 10; Worcester, April 11 ; Yorkshire, April 11 and 13 (the weather fine, with temperature 530, and wind W.); Derbyshire, April 15. Further to the westward, viz., at Llandderfel, in Merionethshire, its appearance was not noticed until the 13th of