HEREDITY 103 



much alike ; and the young of the former species, 

 when able to fly, begin to acquire a new character, 

 namely, the first indication of a rattling cry. The 

 cries of the nestlings of these species are more like 

 that of the adult thrush than that of any other 

 British bird. 



The young nightingale, able to fly, utters a cry 

 exactly like, but less loud than the cry of the 

 young blackbird of the same age. When the male 

 blackbird has lost his mate, or his nest has been 

 destroyed, he utters at intervals a long and plaintive 

 cry, of very high pitch, which, like the shorter cry 

 of the migrating redwing, descends in about the 

 interval of one half-tone. The cry might be whistled 

 thus: 



This note is also uttered by the male blackbird 

 before rain in late autumn, and during prolonged 

 frost in winter. On each of these occasions the 

 robin sometimes utters a note which is the exact 

 counterpart of that of the blackbird, but is much less 

 loud, and is apparently higher in pitch. Dr. Butler 

 writes : " A female robin about to leave her nest, in 

 my garden, uttered the high distress-note, to which 



