Fig. 40.—Transverse section of a portion of the stem of Panicum Crus-galli. × 70
1. Epidermis; 2. sclerenchyma; 3. vascular bundle.
Fig. 41.—Transverse section of the stem of Panicum stagninum. × 10
The cortex outside the band of sclerenchyma is full of air-cavities, small and large. In Panicum colonum the outline of the stem is ellipsoidal with the front quite flat, and the cortex is narrow at the sides and very broad in front and at the back. The sclerenchymatous ring is circular in outline. The stem of Panicum Crus-galli is broadly ovoid and the cortex is uniformly broad. The epidermal cells as well as the lower cells are thickened in the stems of Panicum fluitans and Panicum Crus-galli, but in the stems of Panicum colonum and Panicum flavidum the epidermis alone is thickened. In the cortical portion outside the sclerenchymatous band, small vascular bundles occur in the stems of Panicum colonum, Panicum Crus-galli and Panicum fluitans. (See figs. 39, 40, 42 and 43.)
Fig. 42.—Transverse section of the stem of Panicum fluitans. × 15
