242 NATURAL HISTORY 



16th of April, and then only a pair. Martins in general 

 were remarkably late this year. 



LETTER LIL 



TO THE SAME. 



Selborne, Sep. 9, 1781. 



I HAVE just met with a circumstance respecting swifts, which 

 furnishes 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 about 

 the first day of August, all save one pair, which in two or 

 three days was reduced to a single bird. The perseverance 

 of this individual made me suspect that the strongest of 

 motives, that of an attachment to her young, could alone 

 occasion so late a stay. I watched therefore till the twenty- 

 fourth of August, and then- discovered that, under the eaves 

 of the church, she attended upon two young, which were 

 fledged, and now put out their white chins from a crevice. 

 These remained till the twenty-seventh, looking more alert 

 every day, and seeming to long to be on the wing. After 

 this day they were missing at once ; nor could I ever ob- 

 serve them with their dam coursing round the church in the 

 act of learning to fly, as the first broods evidently do. On 

 the thirty-first I caused the eaves to be searched, but we 

 found in the nest only two callow, dead, stinking swifts, 

 on which a second nest had been formed. This double 

 nest was full of the black shining cases of the hippoloscce 

 kirundinis. 



The following remarks on this unusual incident are obvious. 

 The first is, that though it may be disagreeable to swifts to 

 remain beyond the beginning of August, yet that they can 

 subsist longer is undeniable. The second is, that this un- 

 common event, as it was owing to the loss of the first brood, 

 so it corroborates my former remark, that swifts breed regu- 



