Figure 2. Necklace cells. A Esophagus region (E, left) with cardia (C, middle), showing necklace cells (between arrows); portion of caeca (GC, lower right). The predominantly yellow color of the necklace cells indicates labeling by both RF-I (green) and SCP-I (red). B: RF-I (green) image in plane of axons from one of the two clusters of 3 neurons on the esophagus (upper left) that pass by and possibly make en passant connections with necklace cells (between arrows) in route to the caeca (right).