(a) High magnification of the cell junction between 2 erythroblasts: The electron dense tracer of the extracellular space, tannic acid, decorates the intercellular space. The cytoplasm density of the 2 cells (1 and 2) is unequal, showing that different maturation-stage erythroblasts can be linked together. N, nucleus. Original magnification ×41,400. (b) At a higher magnification, these cell junctions display a septate-like structure (arrowheads). Original magnification ×177,000.