Figure 4.

Electron micrograph of an L. styraciflua minor vein. A, Low magnification micrograph illustrating the arrangement of cell types. The adaxial surface of the leaf is toward the lower left of the figure. SEs and CCs are surrounded by phloem parenchyma (PP) cells. Arrows indicate clusters of plasmodesmata between PP cells and CCs. Bar = 3 μm. B, High magnification of the cluster of plasmodesmata delimited by the rectangle in A. The plasmodesmata are equally branched on both sides. Bar = 0.3 μm.