Aninference enginefor a hybrid representation scheme basedon neurules is presented. Neurulesare a kind of hybridrules that combinea symbolic(productionrules) and a connectionist representation (adaline unit). The inferenceengineusesa connectionisttechnique,whichis basedonthe 'firing potential', a measurementof the firing tendencyof a neurule,andsymbolicpatternmatching.It is proved to be moreefficient and natural than pure connectionistinferenceengines.Explanationof 'how'type canbeprovidedin the formof if-then symbolicrules.