9 3 VARIETY OF FORMS. [CHAP. 



did I not fully feel the force of this truth ; but 

 it will be admitted that the beauty of our woods 

 and fields is due at least as much to foliage as to 

 flowers. 



In the words of the same author, "The leaves of 

 the herbage at our feet take all kinds of strange 

 shapes, as if to invite us to examine them. Star- 

 shaped, heart-shaped, spear-shaped, arrow-shaped, 

 fretted, fringed, cleft, furrowed, serrated, sinuated, in 

 whorls, in tufts, in spires, in wreaths, endlessly ex- 

 pressive, deceptive, fantastic, never the same from 

 footstalk to blossom, they seem perpetually to tempt 

 our watchfulness and take delight in outstripping our 

 wonder." 



Now, why is this marvellous variety, this inex- 

 haustible treasury of beautiful forms ? Does it result 

 from some innate tendency of each species ? Is it 

 intentionally designed to delight the eye of man ? or 

 has the form, and size, and texture, some reference to 

 the structure and organization, the habits and re- 

 quirements, of the whole plant ? 



Ido not propose now to discuss any of the more 

 unusual and abnormal forms of leaves : the pitchers 

 of Nepenthes or Cephalotus, the pitfalls of Sarracenia 

 or Darlingtonia, the spring-trap leaves of Dionaea, 

 the scarcely less effective though less striking con- 

 trivances in our own Drosera or Pinguicula, nor the 

 remarkable power of movement which many leaves 

 present, whether in response to an external stimulus, 

 as in certain species of Mimosa, Oxalis, &c., or as a 

 spontaneous periodic movement, such as the " sleep " 



