n position and enclosing a wide parenchyma is that of _Setaria glauca_.
In the transverse section of the stem the outline is ovate, laterally
compressed, obtusely keeled at the back and somewhat concave in the
front. The sclerenchymatous band is narrow and continuous and very close
to the epidermis, being separated from it only by two or three layers of
thin-walled cells. The epidermal cells alone are thickened. As to the
vascular bundles there are three sets. One set of bundles lying just
outside the sclerenchymatous ring consists of small ones connecting the
ring with the epidermis. Just inside the sclerenchymatous ring lies a
series of bundles which are connected with it. Still inside, at some
distance from the sclerenchymatous band, are seen vascular bundles
forming a row and enclosing a large space of the ground tissue
consisting of only parenchyma. (See figs. 29 and 30.)

[Illustration: Fig. 31.--Transverse section of the stem of Panicum
ramosum x 24]

[Illustration: Fig. 32.--Transverse section of a portion of the stem of
Panicum ramosum. x 75

1. Epidermis; 2. sclerenchyma; 3. vascular bundle.]

[Illustration: Fig. 33.--Transverse section of the stem of Andropogon
caricosus. x 25]

The stem of _Panicum ramosum_ is semi-circular and somewhat flat on one
side. The epidermal cells alone are thickened. There is a broad well
developed continuous band of sclerenchyma, which is connected at regular
intervals with the epidermis by small vascular bundles. Another row of
vascular bundles lies just inside the sclerenchymatous ring and each of
these bundles is in contact with the band. Away from the ring lie a
number of bundles forming a series disposed in two irregular rings
around a broad portion of the ground tissue. (See figs. 31 and 32.)

[Illustration: Fig. 34.--Transverse section of a portion of the stem of
Andropogon caricosus. x 75

1. Epidermis; 2. sclerenchyma; 3. vascular bundle.]

[Illustration: Fig. 35.--Transverse section of a portion of the stem of
Panicum Isachne. x 100

1. Epidermis; 2. sclerenchyma; 3. vascular bundle.]

The stem of the grass _Andropogon caricosus_ is oval in outline, the
front being flat. The epidermal cells and those below and in contact
with them are thick-walled. The sclerenchymatous ring though present is
very narrow and not very conspicuous. It consists of one or two layers
of cells connecting a few vascular bundles forming the outermost set.
There is a series of vascula