Figure 12From: Neuromuscular development of Aeolidiella stephanieae Valdéz, 2005 (Mollusca, Gastropoda, Nudibranchia)Arrangement of serotonergic and FMRFamidergic positive cells within the apical organ in gastropod larvae (redrawn and modified from Page and Parries [74]). Anterior faces upwards and the symbols on the bottom identify the three categories of neurons within the apical organ. The arrow identifies cells within the apical organ that co-express serotonin and FMRFamide. Classification after Ponder and Lindberg [47].Back to article page