178 Popular Delusions in Natural History. [Sess. 



appearance of the swallows during winter, and what could be 

 a more natural supposition than that they passed the cold 

 season of the year in a state of hibernation. As far back as 

 the time of Pliny they were supposed to become torpid in 

 recesses of rocks and mountains, in old towers, under thatched 

 eaves of houses, in hollow trees, and many other similar places, 

 whence they issued on the arrival of the mild breeze of spring. 

 But still more wonderful — they were actually believed to 

 become torpid under water, and to remain during the winter 

 at the bottoms of lakes and pools. Of course in old records 

 we find the same tale as that to which we are so well ac- 

 customed — stories, declarations, affidavits, and sworn state- 

 ments of people who had seen, or maintained they had seen, 

 swallows taken out of holes and other places, even out of 

 water, and which after being placed before a fire revived and 

 flew away ! 



Yet there are not many people who believe such tales 

 nowadays. Birds with their hot blood and rapid circulation 

 one would naturally think to be hardly the best subjects for 

 hibernation ; but their powers of flight have given such of 

 them whose constitutions require a change in winter the 

 means of removal to more genial climes, which is denied 

 to poor creatures like dormice and hedgehogs. Nevertheless 

 the belief is not extinct — the inevitable letters occasionally 

 appear in the ' Field ' telling of swallows that have been 

 found in winter - time or early spring asleep in hollow 

 trees and crevices in cliffs and such places. And the belief 

 has been recently defended by Mr Charles Dixon in a book 

 on the migration of birds, published in 1892, in which, though 

 he rejects as impossible the idea of swallows sleeping during 

 winter under water, he shows a decided tendency to look 

 tenderly on the view that they may hibernate in other situa- 

 tions. The interesting point is that he quotes the opinion 

 of the American ornithologist, Coues, that the American 

 chimney swift (Chastura pelagica) hibernates in hollow trees, 

 because that species is not known to winter out of the United 

 States, nor is it found anywhere in them at that season. But 

 as this species has been found in Mexico and Central America, 

 the supposition — a mere hypothesis at the best — can hardly 

 be said to have any support whatever. 



