tS92- 



Elliot, fnheritatice of Acquired C/ki rncfers. (S( 



witness the birds of Florida or those of the Northwest Coast, as 

 compared with simihir forms in drier sections of our country, and 

 evidence is given upon this point in 'The Entomologist' as stated 



bv Cockerell* that moisture is the cause of a certain phase of 

 melanism, especially among lepidoptera. We may believe that the 

 climatic changes of boreal regions influence the appearance of an- 

 imals that are found within their limits, witness the white cover- 

 ing, aftbrding, during the lengthened winter, an additional means 

 of protection through concealment amid snow and ice. All 



« such evidence strengthens us in the belief that the environment 

 originates variation. Additional evidence of this I obtained in 

 the clever papcrf of my friend, Mr, F. M. Chapman, on a collec- 

 tion of birds from British Columbia, obtained on the coast 

 and in tiie interior. The former is visited by a rainfall heavier 

 than that observed in any other portion of North America, result- 

 ing in a dense forest-growth ; the interior has a minimum of 

 rainfall and vegetation comparatively desert-like in character. 

 "The effect of this rainfall is the production of forms that are 

 darker, more richly colored, or more heavily barred or streaked 

 than any other representative of their respective genera." As a 

 proof of this, thirty-one birds are enumerated from the coast, all 

 of which present these distinguishing characters, when con- 

 trasted with their representatives from the interior, which are 

 paler in every instance. 



An acquired character resulting from the influence of environ- 

 ment will be inherited as long as the causes that produced it re- 

 main the same, but will be extinguished or changed with a 

 changing environment, provided sufficient time has not elapsed 

 for the character to become fixed. In the latter case heredity 

 would probably cause the appearance of the character for several 

 generations at least, even under a changed environment. BaurJ 

 has sliown that Hoflman by isolating the wild carrot and bring- 

 ing it under diilerent conditions changed it considerably, and this 

 change was inherited. Alpine plants removed to a botanical 

 garden acquire new characters. The green Parrot (^C. f estiva)^ 



* Nature, Feb. 27, 1890. 



t Bulletin Am. Mus. Nat. Hist. Ill, No. i, 1890, p. 127. 

 I Amer. Nat. 1891, p. 312. 

 12 



