60 VEGETABLE ORGANOGRAPHY. 



CHAPTER V. 



OF THE CUTICLE AND EPIDERMIS. 



Section I. — General Considerations. 



The name of Cuticle, or Epidermis, has been given 

 to that thin transparent membrane which covers the sur- 

 face of plants, and which is more or less easily separated 

 from the rest of the tissue. Two very opposite opinions 

 have been advanced upon the nature of the Epidermis; 

 the one (and Grew appears to be the first who main- 

 tained it) admits that it is a membrane, properly so 

 called, distinct from the tissue, which it covers; and 

 that it increases with the plant, as the skin of animials. 

 The others (and Malpighi may be considered as the 

 author of this theory) have maintained that the epidermis 

 was only the external cellules of the plant, or, at least, 

 their outer wall become more solid by the action of the 

 air and Kght, by the passage of the juices, and by the 

 effect of evaporation. The partizans of the first opinion 

 maintain that the opaque reticulated lines which are 

 seen on the epidermis, are vessels which form part of, 

 or adhere to it; these Hedwig has named Vasa lym- 

 phatica cuticula. The partizans of the second, think, on 

 the contrary, that the lines are traces of the walls of the 



