SECT. I.] HEREDITARY TRANSMISSION. 83 



geese introduced in Bogota laid at first but few eggs, only one 

 fourth were hatched, and half of these perished. In the second 

 generation the geese began to thrive. Mutilations also are 

 sometimes transmitted. Williamson 1 saw in Carolina, dogs 

 which have been deficient in tails for three or four generations 

 in consequence of one of their ancestors having accidentally 

 lost it. A cow, three years old, which had lost by suppuration 

 her left horn, produced three calves, which instead of the left 

 horn presented only a small protuberance on the skin (Thar). 

 Dogs and horses whose tails or ears are clipped, as the draught 

 dogs in Kamtschatka, 2 often transmit these deficiencies to their 

 offspring (Blumenbach) . This can scarcely surprise us when 

 we consider that even psychical qualities, which have only been 

 acquired in the course of life, are equally transmissible. Wher- 

 ever oxen have not been used as draught animals, it is much 

 more difficult to accustom them to it, than where the custom 

 has existed for some generations (Sturm). This applies also 

 to horses, milch cows, the barking of dogs, and the mewing of 

 cats. Dogs who return to a wild state no longer bark, and 

 cats are said not to mew in America. It is further known that 

 docility is hereditary in dogs, especially in shepherd and hunt- 

 ing dogs. Where fox-hunting is usual, the young foxes are, 

 even without any previously acquired experience, more timid 

 and cautious (Leroy) . Other instances of transmission of ac- 

 quired instinct may be found in Lucas. 3 In many of these 

 cases we must certainly not be too hasty to ascribe to nature 

 what may perhaps be owing to the instinct of imitation, as in 

 the instance cited by Carpenter, 4 that some dogs do not attack 

 the PecaVi singly bdt in packs, whilst others choose the less 

 advantageous mode of attack. That acquired psychical qualities 

 are capable of transmission, by producing a corresponding dis- 

 position in the offspring, cannot be doubted. 



It would be premature to explain the origin of human varie- 

 ties from these observations made on animals; it must, however, 



1 Loc. cit., p. 40. 



2 Langsdorff, " Bemerk. auf e. E. um d. Welt," ii, pp. 236, 1812. 



3 Loc. cit., ii, pp. 479, 482. 



4 Loc. cit., p. 421. 



G2 



