Functional importance of the taste papillae of Phormia regina M.

Electrophysiological recording from taste papillae of Phormia regina M. after stimulation with sugar (sucrose, glucose, fructose and galactose) and salt solutions (NaCl, KCl, KNO3 and CaCl2) has indicated that: 1) in all cases the responses showed a phasic onset about 30 sec in duration; 2) after sugar stimulation the phasic onset of the response was followed by a slow adapting tonic period; 3) no tonic period was present after NaCl, KCl, or KNO3 stimulation; 4) CaCl2 evoked a typical volleying activity that can be explained by a greater spatial spreading of electrotonic currents. These results indicate that the proboscis can only be maintained in an extended position (enabling food to be ingested) by rithmic firing from the papillae.