SWALLOW TRIBE. 41 



and third sets of eggs, produced by those mar- 

 tins which lay several times in a season, it should 

 be recollected, only average three and two re- 

 spectively; and even these may not all be 

 prolific. 



The sand-martin, I believe, has never been 

 suspected of forsaking its progeny ; yet, that it 

 sometimes does abandon them, I have clearly 

 ascertained, by repeated inspections of the nests 

 of this species during the winter months. 



Whether the swift, whose general habits are so 

 very dissimilar to those of the other British hirun- 

 dines, ever deserts its young, I have not been 

 able to determine ; as it is rather a scarce bird in 

 the neighbourhood of Manchester, and usually 

 builds its nest in situations to which I have no 

 access. That this may sometimes happen, how- 

 ever, in cases of extreme urgency, seems proba- 

 ble from an anecdote related by Mr. White, in 

 his Natural History of Selborne, letter 52. " I 

 have just met with a circumstance respecting 

 swifts,'' says that pleasing writer, " which fur- 

 nishes an exception to the whole tenor of my 

 observations, ever since I have bestowed any 

 attention on that species of hirundines. Our 

 swifts, in general, withdrew this year" (1781) 

 " about the first day of August, all save one 



F 



