NOTICEABLE INCIDENTS 63 



as is the habit of the male ; the latter, therefore, 

 has very naturally developed the habit of singing 

 at night, not only when looking for the advent of a 

 mate, but even after she has arrived. Bechstein 

 observed that the nightingales of some districts sang 

 by day, and those of others by night, a local varia- 

 tion which has been several times recorded. Mr. 

 Hudson states that, in a village within an hour of 

 London, the nightingales sing only by day (Birds in 

 a Village, p. 8). 



Yarrell observed that whenever at evening the 

 robin perches high, and begins to sing merrily, the 

 following day will be fair (Brit. Birds, vol. iv. 

 p. 308) ; but I cannot say that I have noticed 

 this as a definite incident, for in autumn the robin 

 habitually sings after a storm, and from an elevated 

 position. The effect of rain is observable in the 

 cries of some birds which, like the house-sparrow, 

 cannot be called singers. Wilson observed that 

 ospreys (Pandion haliaetus] " gambol in the air 

 before a change of weather to rain " ( Am. Orn., 

 vol. ii. p. 115); he also remarked that the great 

 northern diver (Colymbus glacialis] calls much 

 before rain (ibid. vol. iii. p. 1 09) ; and that 

 a woodpecker (Picus pileatus] near rivers is 

 noted for " making a loud and almost incessant 



