HEREDITY 97 



ring-ousel, blackbird, and fieldfare is easily traced. 

 I heard the cry in question uttered by the American 

 robin with much of the manner of the blackbird ; 

 but in the former it is the less prolonged. I have 

 observed this bird in Ottawa and in British Columbia. 

 In size and colour the bird is akin to a hen black- 

 bird. In general habits it resembles that species. 

 So far, I have never heard an analogous cry uttered 

 by the redwing ; but then, the common thrush never 

 utters this cry in winter when the redwing is with 

 us ; and it is very possible that the latter, when 

 defending its young, reverts, like so many other 

 birds, to some cry prevalent in the genus to 

 which it belongs, and therefore probably of remote 

 descent. 



I would draw attention to the great similarity 

 between the mode and occasion of deliverance of the 

 rattling alarm of the blackbird and that of the robin, 

 the only differences being that the alarm of the robin 

 is uttered rather less often during flight, is less loud, 

 and less varied in pitch. The redstart — whose 

 young, like those of blackbird and of robin, are at 

 first of a mottled brown hue on the breast — utters 

 as part of an alarm to its young a sharp snap, sound- 

 ing like the noise made by striking two small pebbles 

 against each other ; when the bird is greatly alarmed 



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