OF THE STEM 
4. 
If a plant be watered by any coloured liquid, the ste*n will, in time, 
ishow that this fluid has ascended into it. There is also in the stem 
a set of vessels to carry downward the juices, which have passed 
through pecuhar processes in the leaves of the plant. 
But of the circulation of fluids in the vegetable substance we shall 
speak more particularly hereafter. Our present object is, to describe 
the external appearance of the vegetable organs, and not their in- 
ternal structure; or, in other words, it is the anatomy and not the 
physiology of plants, which we are now attempting to explain. 
The diflferent kinds of stems have been divided 
into seven classes, as follows — 
Caulis* or proper stem, CwZm, ScapCj Peduncle^ 
Petiole, Frond, and Stipe. 
1st. Caulis, or proper stem, is such as is seen in 
forest trees, in shrubs, and in most annual plants. 
The cauKs is either simple, as in the White hly ; or 
branching, as in the Geranium. The branching is 
the more common form. You have here (Fig. 24 J 
the representation of a caulis, or proper stem (a;) 
Fig. 24. a peduncle, or flower stalk (6 ;) and a petiole, or 
leaf stalk (c.) 
2d. Culm, or straw, (Fig. 25,) is the kind of stem 
which you see in grasses and rushes. The culm 
is either without knots, as in the Bulrush, jointed or 
knotted, as in Indian corn, geniculated, or bent like 
an elbow, as in some of the grasses. Those culms 
which are bent, are also knotted, though they may 
Fig. 25. 
be knotted without being bent. 
The Bamboo, Sugar Cane, and 
various species of Reeds, have 
stems of the culm kind ; some of 
them, particularly the Bamboo, 
are known to attain the height of 
forty feet. 
3d. Scape, (Fig. 26, a, a,) a stalk 
springing from the root, which bears 
the flower and fruit, but not the leaves : 
as the Dandelion, the Cowslip, and the 
Lily of the Valley. Plants with scapes 
are sometimes called stemless plants ; in 
this case, the scape would be consider- 
ed as a peduncle proceeding from the 
root. 
4th. Peduncle, or flower stalk, is but a 
subdivision of the caulis or stem; (See 
Fig. 24, b ;) it bears the flower and fruit, 
but not the leaves ; when the peduncle is divided, each subdivision 
is called a pedicel. In determining the species of plants, we often 
consider the length of the peduncle, compared with the flower; as, 
whether it is longer or shorter. When there is no peduncle or flower 
stalk, the flowers are said to be sessile. 
* This kind of stem is by the French called tige; the i should be sounded like e, 
the f soft like.;, as in teje. The word Ca»:lis is from the Greek Kaulos, a stem. 
4* 
Division of sterr.d— Caulis— Culm— Scape. 
