ACQUIRED CHARACTERS 157 



and none of the fowls has been bhnd unless from 

 fights." 



The myths relatmg to prenatal impressions are 

 the most pathetic of all the inventions of human 

 credulity, and the}^ are as old and as widespread as 

 the inheritance myths to which they are closely re- 

 lated. Jacob's slippery trick with the rods will be 

 long remembered. "And he set the rods which he had 

 pilled before the flocks in the gutters in the watering 

 troughs when the flocks came to drink that they 

 should conceive when thev came to drink. And the 

 flocks conceived before the rods and brought forth 

 cattle ring-streaked, speckled, and spotted." The 

 world is today filled with old wives' tales of pre- 

 natal influences. These mysteries, the ill-begotten 

 offspring of ignorance, have contributed their bane- 

 ful share to the social inheritance. 



It is a strange commentary that, while zoologists 

 have never met with much success in their endeavors 

 to trace the origin of structural changes to the in- 

 heritance of acquired characters, numerous j)i'0" 

 posals have come from physiologists and psycholo- 

 gists. There was some consternation in 1923 when 

 the great Russian physiologist, Pawlow, reported 

 the results of experiments that go far beyond what 

 most Lamarckians have dared hope. Pawlow's con- 

 clusions — and as yet we have only his conclusions — 

 are very surprising. They can best be given in his 

 own words : 



