vii Aristotle on Birds 183 



species. Of the Sparrow, for example, he remarks : 

 " Some persons say that cock Sparrows only live for 

 one year, and adduce as a proof of this the fact that 

 early in the spring there are no birds with the parts 

 beneath the chin black; but later on the black 

 appears, and leads to the inference that none of the 

 former generation have survived. " x 



In other cases he was led into strange blunders, 

 which well illustrate the difficulty of making 

 observations in that day, and the danger of accepting 

 as true what is believed by country people. He 

 tells us that two birds, the Greek names for which 

 we may fairly translate by Eedbreast and Eed- 

 start, change the one into the other, the bird being 

 Eedstart in summer and Eedbreast in winter, a 

 delusion probably arising from the fact that the 

 Eedbreast appears in Greece in the winter, after 

 most of the Eedstarts have gone away southwards. 2 

 He also tells us of two other birds which change into 

 each other in this way, the Black-head and the Fig- 

 bird. 3 We do not know for certain what species he 

 is here alluding to ; but Sundevall thinks he meant 

 the Marsh Tit, which has a black head, and the Pied 

 Flycatcher, which in autumn is not so very unlike 

 the other. Again, he fancied that the Blackbird 

 changed from black to russet in the autumn, 



* H. A. ix. 7. 10. 2 H. A. ix. 49. B. 4. 



3 Ib. 



