Fig. 3. Visualization of hemolymph sinuses/lacunae in the commissural ganglion (CoG) using India ink. India ink injected into the pericardial chamber is incorporated into the circulating fluid and fills blood vessels and sinuses with an easily visualized substrate. As this micrograph shows, the CoG is one of the region of the nervous system possessing vascularization. Here, India ink filling reveals an extensive array of hemolymph lacunae/sinuses within the CoG, including many in the anterior medial quadrant of the ganglion. This image is a digital micrograph of a living ganglion. Abbreviations: coc, circumoesophageal connective; ion, inferior oesophageal nerve; son, superior oesophageal nerve; SoG, supraoesophageal ganglia; TG, thoracic ganglia. Scale bar, 200 µm.