48 
ORGANOGRAPHY, 
BOOK I. 
CHAPTER II. 
OF THE COMPOUND ORGANS IN FLOWERING PLANTS. 
Having now explained the more important circumstances 
connected with modifications in the elementary organs of 
vegetation, the next subject of enquiry will be the manner in 
which they are combined into those masses which constitute 
the external or compound organs, or in other words the 
parts which present themselves to us under the form of roots, 
stems, leaves, flowers, and fruit, and which constitute the ap- 
paratus performing all the actions of vegetable life. In 
doing this, I shall limit myself in the first place to Flowering 
Plants [Introduction to the Natural System, p. I.) ; reserving 
for the subject of a separate chapter the explanation of 
some of the compound organs of Flowerless plants [ibid. 
p. 395.), which differ so much in structure from all others, as 
to require in most cases a special and distinct notice. 
Sect. I. Of the Cuticle and its Appendages. 
I. Of the Epidermis. 
Vegetables, like animals, are covered externally by a thin 
membrane or epidermis, which usually adheres firmly to the 
cellular substance beneath it. To the naked eye it appears 
like a transparent homogeneous skin, but under the micro- 
scope it is found to be traversed in various directions by lines, 
which, by constantly anastomosing, give it a reticulated cha- 
racter. In some of the lower tribes of plants, consisting 
entirely of cellular tissue, it is not distinguishable, but in all 
others it is to be found upon every part exposed to the air, 
except the stigma and the spongelets of the roots. It is, 
however, as constantly absent from the surface of parts which 
