2 MINUTES OF 



On the Structure oj Vegetables. 



1. The Epidermis, or cuticle, is the first thing that presents itself to our 

 view. It is a thin jiaembrarie, formed of fibres that cross each other in evei-y di- 

 rection, with horizontal perforations. Its texture is sometimes so thin, that the 

 direction of the fibres becomes visible, by holding it against the light. The use 

 ipf^lie epidermis is to defend the cortex, which lies next to it, from the injuries 

 of the air; to keep open, by its callous nature, the pores of the exhaling and in- 

 haling vessels; to modify the impressions of external obje6ls upon the vegetable; 

 to protect the extreme ramifications of the aerial or aqueous vessels; and to cover 

 the cellukr substance, in which the several fluids are elaborated. 



When the epidermis is destroyed in the living plant, it is regenerated; ad- 

 heres more firmly to the cortex, and forms a kind of cicatrix' or scar. 



The Epidermis of the Bark, necessarily acts to vegetables, as the Mouth or 

 organ for the selection and introsusception of food. It is exceedingly fine and 

 close in its mechanical texture; for, it is perhaps destined to perform not a che- 

 mical, but a mechanical part; and that mechanism muft, of course, be extremely 

 fine, which shall, in the relative situation of the epidermis of the bark, exclude 

 every matter that might injure the interior organization of the vegetable. 



2. The Cortex or outer bark, is situated next to the epidermis, is of a hard 

 texture, and loosely adheres in trees to the next covering or liber; but in tender 

 plants it is soft, and called the cutis, skin, or cellular coating. It is the first recep- 

 tacle and the refervoir of the food taken in by the Epidermis, Its texture consists 

 of vesicles and utricles, so very nutnerous, and so close together, as to form a 

 continued coating. In its vesicles and utricles, which run horizontally, is that 

 food deposited for digestion and nutritive distribution. In them, begins the che- 

 mical process by which the living vegetable digests its food into a proper addition 

 to the substance of its organs. The mechanical relations and poAvers of the organs 

 and of the food, are made to co-operate with those which are chemical. In its 

 passing from the utricles and vesicles of the cellular tissue, tlirough the organs 

 of the cortical coating, — the Sap, the general chi/le or blood of the plant, is com- 



