Birds of Fortwilliam Park. 39 



been heard to repeat its song 300 times in an hour. 



The skylark used to nest regularly in the Park, but has now 

 ceased to do so. The autumnal movements of that bird are 

 very interesting, chiefly from the enormous numbers sometimes 

 seen. Night and day for several days together armies of larks 

 pass inland into England. Mr. Seebohm found himself one 

 night on Heligoland surrounded by a "drifting sea" of these 

 birds ; clouds of them, he said, emerged in an unbroken stream 

 from the darkness, and during the two hours he watched, the 

 " rush" went steadily on. 



The swifts' power of flight is simply marvellous. It has been 

 known to remain on the wing for sixteen hours at a stretch, and 

 its estimated rate of flight is 270 miles an hour, a speed which 

 if maintained would take it from London to New York in eight 

 hours ; so that from Madrid to London, a distance of 780 miles, 

 would be only a pleasant little evening excursion, It is not 

 thought, however, that the bird comes straight to us from its 

 winter quarters. It has a habit of " lingering by the way," and 

 swifts on migration sweeping one day over the olive gardens of 

 Spain are probably found a week later circling round the oaks 

 of Old England. 



The cuckoo's curious habit of depositing its eggs in the nests 

 of other birds was dwelt upon at length. It lays five eggs in 

 the season, at intervals of seven or eight days. The cuckoo 

 cannot rear its own young. Young cuckoos are such gluttons 

 it would be impossible for any mother to find sufficient food for 

 five of them. The male cuckoo is also exceedingly voracious, 

 and entirely occupied in feeding himself. Again, the young 

 birds in the same nest would be of widely different ages, which 

 would lead to still further complications ; so the cuckoo cuts 

 the Gordian knot. It places its eggs, one in each, in the nest 

 of some insectivorous bird, mostly the meadow-pipit. The 

 cuckoo presents an interesting case of protective mimicry. It 

 is one of the most defenceless of birds, being of very weak struc- 

 ture, and its resemblance to a hawk no doubt protects it from 

 attack. 



The wood-pigeon has no alarm note, and Mr. Dickson had 



