SWALLOW TRIBE. 49 



viduals of their species, too young or feeble to 

 undergo tlie fatigues of migration, merely dor- 

 mant ? The advocates of torpidity will do well 

 to consider this difficulty with attention, since, 

 if not removed, it leaves them no alternative but 

 to renounce, as untenable, the doctrine they 

 maintain. 



APPENDIX. 



Since the foregoing observations on the occa- 

 sional desertion of their last hatched broods, by 

 several species of British hirundines, were sub- 

 mitted to the consideration of the society, a 

 favourable opportunity of pursuing the investi- 

 gation has again presented itself. 



On the departure of the house-martins, in 

 October, 1826, it was perceived, that they left 

 some broods to perish in the nests built under 

 the eaves of a bam, situated at the Hill-top, in 

 the chapelry of Blakeley ; the edifice being the 



