THEORIES OF EVOLUTION 23 



the descendants of the queen bee were supposed to reproduce 

 the modifications of the workers associated with her. It is 

 as though the offspring of Brown were supposed to reproduce 

 the acquired peculiarities of Jones and Robinson. A modi- 

 fication of a man's thumb (e. g. an effect of use) is supposed 

 to affect his germ-cells, situated far distant, in such a peculiar 

 manner that the modification tends to be reproduced as an 

 inborn trait by his offspring. A different modification of his 

 thumb (e. g. an effect of injury) is supposed to affect the 

 germ-cell differently, but also in such a precise way that it 

 likewise tends to be reproduced. A similar change (e. g. an 

 effect of injury) in the great toe is supposed to affect the 

 germ in a manner so profoundly different, that the peculiarity 

 is reproduced, not in the thumb, but in the great toe of the 

 offspring and so on ad infinitum. 



38. It will be seen at once that this power of transmitting 

 acquirements which multicellular organisms are said to 

 possess is if it exists a very remarkable thing. A high 

 organism may make a million different acquirements in 

 mind, brain, gland, muscle, bone, skin in every structure. 

 Each of them is supposed to affect the germ-plasm in which 

 there is neither mind nor brain nor skin, nor any other 

 specialized tissue, in such a very special and peculiar way 

 that the extremely remote cell-descendants of that germ 

 will reproduce the change, not as an acquirement, but as 

 something very different, as a variation. We must therefore 

 ask ourselves three questions. How did this remarkable 

 power, or rather infinity of powers, arise in nature ? What 

 is the machinery by which it works ? What evidence is 

 there of its existence ? 



39. How did it arise ? Nothing like it exists, of course, 

 among unicellular forms, which, since they separate, are 

 unable to influence one another. It must have arisen, if 

 at all, de novo amongst multicellular organisms. What then 

 caused the evolution of it ? What preserves it ? If we rule 

 out miracle there remains only Natural Selection. But we 

 have already seen that Natural Selection and the transmis- 

 sion of acquirements are frequently not compatible. Since 

 the one works by injurious and the other by beneficial 

 agencies, they pull in opposite directions. Suppose for the 

 moment we accept both doctrines as true. Then, when 

 Natural Selection is causing evolution by the elimination of 

 the unfit, the transmission of acquirements is causing 

 degeneration by the inherited effects of injuries (e.g. the 

 effects of want and disease). Or when the transmission 



