Fig. 2.

Schematic of fully dissected experimental preparation. The cpv1a and cpv1b muscles originate on the hypodermis/carapace (large ovals) very near each other, insert on different but closely apposed stomach ossicles (small ovals), and thus are closely apposed along their entire length. Muscle contractions were measured by attaching an isotonic transducer to the hypodermis between one or both muscle pairs with a wire hook. The muscles are innervated via the dorsal ventricular (dvn), lateral ventricular (lvn), dorsal lateral ventricular (dlvn), and gastropyloric (gpn) nerves. The cell bodies of the neurons that innervate the muscles are located in the stomatogastric ganglion (STG). Other important nerves for this work are the pyloric dilator nerve (pdn), which contains the axons of the PD neurons, and the aln, which contains the axons of the GM neurons. mvn, Median ventricular nerve;stn, stomatogastric nerve.