OF SELBOUNE. l/l 



LETTER XL. 



TO THE SAME, 



DEAR SIR; Selborne, Sept. 2, 1774. 



Before your letter arrived, and of my own 

 accord, I had been remarking and compar- 

 ing' the tails of the male and female swal- 

 low, and this ere any young broods ap- 

 peared : so that there was no danger of 

 confounding the dams with their pulli : and 

 besides, as they were then always in pairs, 

 and busied in the employ of nidification, 

 there could be no room for mistaking the 

 sexes, nor the individuals of different chim- 

 nies the one for the other. From all my 

 observations, it constantly appeared that 

 each sex has the long feathers in its tail 

 that give it that forked shape j with this 

 difference, that they are longer in the tail 

 of the male than in that of the female. 



Nightingales, when their young first 

 cume abroad, and are helpless, make a 



