VI PREFACE. 



Tieghein, Strasburger, Lawes and Gilbert, McNab, Vesque, Rau- 

 wenhoff, Warming, and many others whom it is not possible to 

 specify in a work of this character. 



Comparatively few alterations have been made to the chapters 

 on Geographical and Geological Botany, which, for their effective 

 treatment, would require another volume. The additions in these 

 subjects have been chiefly derived from the writings of Hooker, 

 Grisebach, Tchihatchef, Williamson, Crepin, and Carruthers. 



Some additional woodcuts have been supplied, whose source is 



acknowledged in the text. 



M. T. M. 



March 1878. 



