ORDER PASSERES. 87 



their feet soon after became swelled and inflamed, which 

 Mr. P. attributed to their perching, and they died about 

 Christmas ; thus the first year''s experiment was in some 

 measure lost. Not discouraged by the failure of this, 

 Mr. P. determined to make a second trial the succeeding 

 year, from a strong desire of being convinced of the truth 

 respecting their going into a state of torpidity. Accordingly, 

 the next season, having taken some more birds, he put them 

 into the cage, and in every respect pursued the same method 

 as with the last ; but to guard their feet from the bad effects 

 of the damp and cold, he covered the perches with flannel, 

 and had the pleasure to observe that the birds throve ex- 

 tremely well ; they sung their song through the winter, and 

 soon after Christmas began to moult, which they got through 

 without any difficulty, and lived three or four years, regu- 

 larly moulting every year at the usual time. On the renewal 

 of their feathers, it appeared that their tails were forked ex- 

 actly the same as in those birds which return hither in the 

 spring, and in every respect their appearance was the same." 



M. Natterer has also kept a number of swallows in cages 

 for eight or nine years together, and has observed that they 

 all moulted abovit the month of February, the period when 

 these birds having quitted Europe, are found in the warmer 

 countries of Africa and Asia. It is obvious that their moult- 

 ing at this period is irreconcilable with the idea that they 

 hibernate in this country under Avater. 



The activity of these birds, as the period of their emigra- 

 tion approaches, is very amusing, and we have a fine oppor- 

 tunity, especially on the southern shores of our oAvn island, 

 of witnessing their departure in many and numerous flocks. 

 For some days* previously to their quitting our shores, they 

 may be seen in clusters so thick, sticking to the walls and 

 sides of houses and elevated buildings, as to hide, even at a 

 small distance, all appearance of that on which they rest, till 

 at last they all quit together, and fly for a time east or west, 



