ANNOTATIONS AND ADDITIONS. 367 



POSTSCRIPT 



ON THE 



PHYSIOGNOMIC CLASSIFICATION OF PLANTS. 



IN the preceding sketch of a " Physiognomy of Plants/ 7 I have 

 had principally in view three nearly allied subjects : the absolute 

 diversity of forms; their numerical proportion, i. e. their local 

 predominance in the total number of species in phsenogamous floras; 

 and their geographic and climatic distribution. If we desire to rise 

 to general views respecting organic forms, the physiognomy of plants, 

 the study of their numerical proportions (or the arithmetic of bo- 

 tany), and their geography (or the study of their zones of distri- 

 bution), cannot, as it appears to me, be separated from each other. 

 In the study of the physiognomy of plants, we ought not to dwell 

 exclusively on the striking contrasts presented by the larger organic 

 forms separately considered, but we should also seek to discern the 

 laws which determine the physiognomy of Nature generally, or the 

 picturesque character of vegetation over the entire surface of the 

 globe, and the impression produced on the mind of the beholder by 

 the grouping of contrasted forms in different zones of latitude and 

 of elevation. It is from this point of view, and with this concen- 

 tration or combination of objects, that we become aware, for the 

 first time, of the close and intimate connection between the subjects 

 which have been treated of in the foregoing pages. We are here 

 conducted into a field which has been as yet but little cultivated. 

 I have ventured to follow the method first employed with such 

 brilliant results in the Zoological works of Aristotle, and which is 

 especially suited to lay the foundation of scientific confidence a 



