V. 



6EQU0IA AND ITS HISTORY; THE RELATIONS OF NORTH 

 AMERICAN TO NORTHEAST ASIAN AND TO TERTIARY 

 VEGETATION. 



(A Presidential Address to the American Association foe the Advance- 

 ment of Science, at Dubuque, August, 1S72.) 



TnE session being now happily inaugurated, your 

 presiding officer of the last year has only one duty to 

 perform before he surrenders the chair to his success- 

 or. If allowed to borrow a simile from the language 

 of my own profession, I might liken the President of 

 this Association to a biennial plant. He flourishes for 

 the year in which he comes into existence, and per- 

 forms his appropriate functions as presiding officer. 

 When the second year comes round, he is expected to 

 blossom out in an address and disappear. Each presi- 

 dent, as he retires, is naturally expected to contribute 

 something from his own investigations or his own 

 line of study, usually to discuss some particular scien- 

 tific topic. 



Now, although I have cultivated the field of North 

 American botany, witli some assiduity, for more than 

 forty years, have reviewed our vegetable hosts, and 

 assigned to no small number of them their names and 

 their place in the ranks, yet, so far as our own wide 

 country is concerned, I have been to a great extent a 



