msTORlGAL 8KET0S. XT 



that hypothesis which supposes the species living at any 

 time to be the result of the gradual modification of pre- 

 existing species, a hypothesis which, though unproven, and 

 sadly damaged by some of its supporters, is yet the only 

 one to which physiology lends any countenance; their 

 existence would seem to show that the amount of modifica- 

 tion which living beings have undergone during geological 

 time is but very small in relation to the whole series of 

 changes which they have suffered." 



In December, 1859, Dr. Hooker published his " Intro- 

 duction to the Australian Flora." In the first part of this 

 great work he admits the truth of the descent and modifica- 

 tion of species, and supports this doctrine by many original 

 observations. 



The first edition of this work was published on E'ovem- 

 ber 24, 1859, and the second edition on January 7, 1860. 



