Fluorescence staining of bag cell clusters, showing the distribution of cell nuclei, BCCa-I, and BCCa-II. Neighboring 12 μm tissue sections through the abdominal ganglion were stained essentially as indicated in Figure 5, except that the preincubation reactions were not subjected to ultracentrifugation. Sections were also counterstained with the nuclear dye bisbenzimide to reveal the positions of cell bodies. Photographs show stained bag cell clusters (BC) and the nerve tracts of the pleural-abdominal connective (PA). A, αBCCa-II staining of a bag cell cluster. The antibody was preadsorbed with a 25-fold molar excess of FP-I. B, Bisbenzimide staining of the same bag cell cluster in a neighboring section showing the large nuclei of the bag cell neurons surrounded by smaller glial nuclei. C, αBCC-I staining of the same section shown in B. The antibody was preadsorbed with a 25-fold molar excess of FP-II. Scale bar, 200 μm.