96 NATURAL HISTORY OF SELBORNE. 



imitative of several birds ; as the sparrow, swallow, skylark. 

 When it happens to be silent in the night, by throwing a 

 stone or clod into the bushes where it sits you immediately 

 set it a-singing ; or, in other words, though it slumbers 

 sometimes, yet as soon as it is awakened it reassumes its 

 song. 



LETTER XL. 



SELBOENE, Sept. 2nd, 1774. 



BEFORE your letter arrived, and of my own accord, I had 

 been remarking and comparing the tails of the male and 

 female swallow, and this ere any young broods appeared ; 

 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 

 chimneys 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 ; with this 

 difference, that they are longer in the tail of the male than 

 in that of the female. 



Nightingales, when their young first come abroad, and 

 are helpless, make a plaintive and a jarring noise ; and also 

 a snapping or cracking, pursuing people along the hedges as 

 they walk : these last sounds seem intended for menace and 

 defiance. 



The grasshopper-lark chirps all night in the height of 

 summer. 



Swans turn white the second year, and breed the third. 



