In most insects the contact chemosensory sensilla are separated into two compartments, one containing the dendrites of the receptor neurones and one dendritic free lumen. Two types of pores occurring in these sensilla were reported in literature, one primary pore, situated distally, that permits gustatory neurones to contact outside media and a secondary type that either connects both compartments or connects the dendritic free lumen with the outside. On the basis of anatomy of the gustatory sensilla, two electrical models have been constructed; 1. a unipore model assuming the exclusive existence of a primary pore and 2. a multipore model assuming both types of pore being present. Comparing theoretical predictions of the models it is concluded that multipore theory fits well to experimental evidence, whilst unipore theory must be rejected. Furthermore, evidence is obtained that the secondary pore connecting both compartments is present. The significance of the secondary type of pore is discussed.