158 NATURAL HISTOKY 



duo proportion of each sex, it should seeni very improbable 

 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 

 chaffinches (Fringillce ccelebes) , for some good purposes, 

 have a peculiar migration of their own in which 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 docs, the sexes herd separately, except at the season 

 when commerce is necessary for the continuance of the 

 breed. For this matter of the chaffinches see "Fauna 

 Suecica," p. 85, and " Systema Nature," p. 318. I see 

 every winter vast flights of hen chaffinches, but none of 

 cocks. 1 



Your method of accounting for the periodical motions of 

 the British singing birds, or birds of flight, is a very 

 probable one ; since the matter of food is a great regu- 

 lator of the actions and proceedings of the brute creation : 

 there is but one that can be set in competition with it, and 

 that is love. But I cannot quite acquiesce with you in one 

 circumstance, when you advance that, " when they have 

 thus feasted, they again separate into small parties of five 

 or six, and get the best fare they can within a certain 

 district, having no inducement to go in quest of fresh- 

 turned earth." Now, if you mean that the business of 

 congregating is quite at an end from the conclusion of 

 wheat- so wing to the season of barley and oats, it is not the 

 case with us ; for larks and chaffinches, and particularly 

 linnets, flock and congregate as much in the very dead of 

 winter as when the husbandman is busy with his ploughs 

 and harrows. 



Sure there can be no doubt but that woodcocks and 

 fieldfares leave us in the spring, in order to cross the seas, 

 and to retire to some districts more suitable to the purpose 

 of breeding. That the former pair before they retire, and 

 that the hens are forward with egg, I myself, when I was a 



1 See Letter XIII. to Pennant, p. 47, note L ED. 



