214 THE HISTORY OF CREATION. 



weeping willows, etc. The transmission of acquired diseases, 

 such as consumption, madness, and albinism, likewise form 

 very striking examples. Albinoes are those individuals who 

 are distinguished by the absence of colouring matter, or 

 pigments, in the skin. They are of frequent occurrence 

 among men, animals, and plants. In the case of animals of 

 a definite dark colour, individuals are not unfrequently born 

 which are entirely without colour, and in animals possessing 

 eyes, this absence of pigment extends even to the eyes, so 

 that the iris of the eye, which is commonly of a bright or 

 intense colour, is colourless, but appears red, on account of 

 the blood-vessels being seen through it. Among many 

 animals, such as rabbits and mice, albinoes v/ith white fur 

 and red eyes are so much liked that they are propagated in 

 great numbers as a special race. This would be impossible 

 were it not for the law of the transmission of adaptations. 



Which of the changes acquired by an organism are trans- 

 mitted to its descendants, and which are not, cannot be 

 determined a priori, and we are unfortunately not ac- 

 quainted with the definite conditions under which the 

 transmission takes place. We only know in a general way 

 that certain acquired qualities are much more easily trans- 

 mitted than others, for example, more easily than the 

 mutilations caused by accidents. These latter are generally 

 not transmitted by inheritance, otherwise the descendants of 

 men who have lost their arms or legs would be born without 

 the corresponding arm or leg; but here, also, exceptions 

 occur, and a race of dogs without tails has been produced 

 by consistently cutting off the tails of both sexes of the dog 

 during several generations. A few years ago a case occurred 

 on an estate near Jena, in which by a careless slamming of 



