43 
OF THE STEM. 
5th. Petiole , or leaf stalk, is a kind of stem, like a fulcrum, sup¬ 
porting the leaf, as the 'peduncle supports the flower; it is usually 
green, and appears to be a part of the leaf itself. The petiole of 
many plants is somewhat in the form of a cylinder ; but the upper 
surface is rather flattened, the under surface convex. You will find 
this remark tiseful, in distinguishing the foot-stalks of compound 
leaves from young branches, with which they are sometimes con¬ 
founded. In most cases, the leaves and flowers are supported by 
distinct foot-stalks, but sometimes the foot-stalk supports both the 
leaf and flower. The Petiole is often compared with the leafj as the 
peduncle is with the flower, as to its relative length, in the different 
species. 
Fig. 27. 
^ 6th. Frond. (Fig. 27.) The terra 
frond, belongs entirely to Cryptoga- 
mous plants. This term however is ap- 
^ plied to the leaf rather than the stem ; 
in this sketch of the fern, the leafy part, 
6, is the frond ; this bears the flower and 
fruit. Linnaeus considered the leaves 
of palm-trees as fronds ; we shall here¬ 
after remark upon the different internal 
structure of their stems from those of 
the oak and other plants which are 
termed cauline -, because their stem is a 
caulis. Plants with fronds are mono- 
cotyledonous. 
7th. Stipe., The stem of the fern (Fig. 27, a,) is called a stipe. By 
observations of geologists it is ascertained that stiped plants were 
created before cauline ones; petrifactions of the former being found 
in the lower formations of the earth, while no remains of cauline 
Fig. 23. plants are ever found there. The stalk of a fungus or 
mushroom is called a stipe. The term is also applied to 
the slender thread, which in many of the compound flow- 
c ers, elevates the hairy crown with which the seeds are 
furnished, and connects it with the seed. Thus, in a seed 
a of the Dandelion, which is here represented, the column 
7 (Fig. 28, ci.) standing on the seed (b.) and elevating the 
h down (4) is the stipe. 
Here is a mushroom with the cap (Fig. 2 9 T d,) 
elevated on its stipe (e.) 
Branches. The stem is either simple , or divided 
into branches. The branches are parts of the 
plant which proceed immediately from the 
trunk ; the division of these are called branch- 
Fig. 29. lets ; a diminutive appellation, which means a 
little branch. These parts resemble, in their 
formation, the trunk or stem, which furnishes 
them; the branch may be considered as a tree, 
implanted upon another tree of the same species. 
Branches sometimes grow without any apparent 
order in their arrangement; sometimes they 
are opposite ^ sometimes alternate; and sometimes, as in the pine, 
they form a series of rings around the trunk. Some branches 
Peduncle—Petiole—Frond—Which part of the fern is its frond?—Which the stipe? 
—Difference between aliped and cauline plants—Which first formed ?—Different ap¬ 
plications of the term stipe—Stipe of a dandelion seed—Stipe of a mushroom— 
Branches—Branchlets—Yarious appearances of branches. 
