38 EVOLUTION OF BIRD-SONG 



during combat. The house -sparrow is generally 

 silent when fighting. The so-called noisy combats 

 of this species are simply assemblies of males 

 around a female, to whom they are showing-off 

 and chirping, and from whom they often receive 

 violent pecks and pinches which sometimes make 

 some of them scream. When males fight, one may 

 hurt the other and cause him to cry out. This one 

 then exclaims in precisely the same tone as that 

 employed when a sparrow is carried away by a 

 hawk ; but until so injured by an opponent he is 

 silent. The females sometimes severely pinch 

 males which play to them too demonstratively : I 

 have twice seen a male hanging suspended for 

 certainly two seconds by the bill of a female. 



The crested lark (Alauda cristatus), like the sky- 

 lark, " has the peculiarity that when it fights it con- 

 tinues to sing " (Bechstein's Nat. Hist, of Cage Birds, 

 p. 1 79). I have heard the full song of the tree-pipit 

 repeated by this bird when fighting furiously. During 

 spring and summer male thrushes sing when fighting, 

 and during the whole year, excepting July and 

 August, male robins have the same habit ; in both 

 species the song becomes raised in pitch, often to an 

 obscure squeak, before the combat commences. Jesse 

 observed this habit in the robin (Gleanings, 2nd 



