132 NATURAL HISTORY 



little walled court belonging to the house where I now am 

 visiting, retires under ground about the middle of November, 

 and comes forth again about the middle of April. When it 

 first appears in the spring it discovers very little inclination 

 towards food ; but in the height of summer grows voracious : 

 and then as the summer declines it's appetite declines; so that 

 for the last six weeks in autumn it hardly eats at all. Milky 

 plants, such as lettuces, dandelions, sowthistles, are it's fa- 

 vourite dish. In a neighbouring village one was kept till by 

 tradition it was supposed to be an hundred years old. An 

 instance of vast longevity in such a poor reptile ! 



LETTER VIII. 



TO THE SAME. 



Selborne, Dec. 20, 1770. 

 DEAR SIB, 



THE birds that I took for aberdavines were reed-sparrows 

 (pas seres torquati.) 



There are doubtless many home internal migrations within 

 this kingdom that want to be better understood: witness those 

 vast flocks of hen chaffinches that appear with us in the 

 winter without hardly any cocks among them. Now was 

 there a due proportion of each sex, it should seem very im- 

 probable that any one district should produce such numbers of 

 these little birds ; and much more when only one half of the 

 species appears: therefore we may conclude that the frmgillce 

 ccelebes, for some good purposes, have a peculiar migration of 

 their own in winch the sexes part. Nor should it seem so 

 wonderful that the intercourse of sexes in this species of birds 

 should be interrupted in winter ; since in many animals, and 

 particularly in bucks and does, the sexes herd separately, 

 except at the season when commerce is necessary for the 

 continuance of the breed. For "this matter of the chaffinches 

 roe .Fauna Suecica, p. 85, and Systema Natures, p. 318. I see 

 every winter vast flights of hen chaffinches, but none of cocks. 



