854 : Banffshire Fauna. [ APPENDIX. 
end of August or beginning of September, and it returns about 
the middle of May; the sand-martin next, or about the second 
or third week in September, and it usually returns about the 
third week in April; and the swallow and house-martin com- 
monly about the first week or middle of October, and they re-ap- 
pear about the Ist of May. Before I part with this interesting 
tribe I must become a little arithmetical. We are frequently 
told, and justly, of the great benefit swallows and other insect- 
feeders do, by the countless herds of noxious creatures which 
they destroy. I will relate an instance of my own experience in 
this respect. Picking up a swallow which had been shot by a 
friend, I found that its mouth was crammed with gnats and flies. 
Some of them were alive. They all seemed attached to the mouth 
by a glutinous fluid. The bird had apparently been catering for 
its young. Being desirous of nfaking a further examination, I 
wrapped it in paper and put it in my pocket. On reaching home 
I opened the paper, when a number of the gnats buzzed out into 
my face, much to my regret; but I succeeded in counting up- 
ward of 70, and I am quite sure there were more than 100 in 
all. Now, it is a well-known fact that both birds assist in rear- 
ing their young. Well, say that they visit the nest every ten min- 
utes (which is under the mark), and that every time of doing so 
each bird conveys 70 insects; this in an hour amounts to 840; 
in a day of twelve hours, which is but a short day for a swallow 
at that season of the year, to 10,080; in a week of seven days, to 
70,560; and in a fortnight, to 141,120. But if we carry the cal- 
culation a little farther, by supposing that the birds rear two 
broods in a season, although the number is often three, we have, 
at the ratio at which we have been counting, a total of 282,240 
insects destroyed in one year by two birds alone, while rearing 
their two broods! 
Caprimuteus Evropzus [Wightjar]. 
Of late years this species would appear to havépecome more nu- 
merous, but it is still very far from plentiful. ‘ 
CotumBa PaLumBus [Ring-dove]. ‘ 
Or, as we have it, Cushie Doo. This bids fair to become one of the 
greatest pests of the farmers. The wild pigeons have increased 
amazingly within the last few years, and the damage they do is 
incalculable. This increase is caused by the almost total destruc- 
tion of the hawk tribe, which tended greatly to thin their numbers. 
CotumBa Livia [Rock Dove]. 
A few pairs breed in the caverns along our coast. It is a rare case, 
