"Nervous system of Astacus fluviatilis. bg, sub-oesphageal ganglion; cs, commissural ganglion; g, brain; s, visceral nerve; sc, oesophageal connective; y, post-oesophageal commissure; IV-VIII, thoracic ganglia; 1-6, abdominal ganglia." -Parker, 1900

Crayfish Nervous System

"Nervous system of Astacus fluviatilis. bg, sub-oesphageal ganglion; cs, commissural ganglion; g, brain;…