FOWLS' WINGS. 6 1 



mixia, correlation, and the effects of use and 

 disuse during lifetime, and still regard the case 

 of the domestic duck as a valid proof of the 

 inheritance of the effects of use and disuse, we 

 must also accept it as an equally valid proof that 

 the effects of use and disuse are not inherited. 

 Nay, we may even have to admit that, in two 

 points out of four, the inherited effect of use and 

 disuse on successive generations is exactly opposite 

 to the immediate effect on the individual. 



Among fowls the wing-bones have lost much 

 in weight but little or nothing in length which is 

 the reverse of what has occurred in ducks, although 

 disuse is alleged to be the common cause in both 

 cases. Some of the fowls which fly least have 

 their wing-bones as long as ever. In the case of 

 the Silk and Frizzled fowls ancient breeds which 

 " cannot fly at all " and in that of the Cochins, 

 which " can hardly fly up to a low perch," Darwin 

 observes " how truly the proportions of an organ 



