24 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



of acquired characters. It can only be alluded to here as 

 one of the absorbing problems of our time, and was well 

 handled by Professor Herdman in his presidential address 

 before this Society in 1888. Its truth or partial truth will 

 probably still remain a question of evidence. In spite, 

 however, of much pains taken in the matter by many 

 naturalists, I am not aware that any case has been 

 satisfactorily proved in which a character acquired during 

 the life of an organism has been transmitted to its 

 descendants, while there is an enormous array of evidence 

 tending to the belief that inborn, germinal, or constitu- 

 tional variations alone are transmitable. 



Meanwhile, many theories of heredity have been in the 

 air, the most notable of them being those formulated by 

 Herbert Spencer, Darwin, Francis Galton, and W. K. 

 Brooks, to whose writings on the subject I need only to 

 refer those interested in the subject. 



In spite of Eedi's conclusive experiments made as far 

 back as 1668, spontaneous generation, or the belief that 

 under certain conditions the non-living could be converted 

 into the living, continued to be widely held during the 

 earlier part of the Victorian Era. It was a well-known 

 axiom of ancient science that the corruption of one thing 

 is the birth of another, from the general belief that a 

 seed dies before the young plant springs from it. Paul 

 expressed a belief that was universally held 1800 years 

 ago, when he said, " Thou fool, that which thou sowest is 

 not quickened except it die," this belief remaining accepted 

 down to the seventeenth century. 



Schwann in 1837, Helmholz in 1843, and Schroder in 

 1859 showed, experimentally, that air after passing through 

 red hot tubes, or through a close membrane of cotton wool, 

 was deprived of something which caused fermentation or 

 putrescence before being so treated; and Tyndall later 



