XVI PLAN OF THE WORK. . 



Hamel, Hales, Hedwig, Gaertner, Comparetti, Kroc- 

 ker, Mirbel, Link, Rudolphi, Treviranus, Moldenhewer, 

 Kieser, Turpin, Sennebier, Spallanzani, Darwin, Keith, 

 Ellis, Knight, Dutrochet, Amici, Adolphe Brongniart, 

 Girou de Busaraingues, and a few others. It is honour- 

 able to our own country to have produced such able 

 observers and experimenters as Grew, Hales, Ellis, and 

 T. A. Knight. I leave it to others to give a similar 

 list of the Systematists, who can never stand in a 

 higher rank than mere pioneers, whose labours are 

 indispensably necessary to the philosophers in the 

 higher departments of the science. 



Bonn on the Rhine, 

 July 20th, 1832. 



