Callus and suspension cultures ofMelissa officinaliscould not accumulate detectable amounts of volatile constituents typical of the intact plant when maintained under varying cultural conditions. Non-terpenoid constituents, especially furfural, hexanoic and octanoic acids, were accumulated by the callus tissues. Similar accumulation was observed for the suspended cells in addition to other minor products which were both released into the liquid medium. The petrol extract of the cultures yielded predominantly C14H30to C17H36alkanes and β-sitosterol.