Fig. 1.4.3.01. A dendritic filopodium (F) extends from the shaft of a dendrite (D). The filopodium has a dark, grainy cytoplasm as compared with the cytoplasm of the dendrite. Note the growth cone (asterisk) of a different axon or dendrite nearby. ES - extracellular space. Scale = 1 µm. (4 day-old rat, hippocampus area CA1.)