Described are bicyclic lactones, both fused ring lactones defined according to the generic structure: ##STR00001## and spiro lactones defined according to the generic structure: ##STR00002## uses thereof in augmenting, enhancing or imparting aromas in or to perfume compositions, perfumed articles, colognes and perfumed polymers; processes for preparing such bicyclic lactones and intermediates therefor.In the structure: ##STR00003## Z is one of the moieties: ##STR00004## one of R.sub.1 or R.sub.3 is methyl and the other is hydrogen; and R.sub.4, R.sub.5, R.sub.6, R.sub.7, R.sub.8 and R.sub.9 hydrogen or nonadjacent C.sub.1 C.sub.3 alkyl. In the structure: ##STR00005## Y represents C.sub.2 C.sub.12 substituted or unsubstituted alkylidenyl, alkenylidenyl or alkadienylidenyl having the structure: ##STR00006## and completes a C.sub.5 C.sub.15 cycloalkyl, cycloalkadienyl or cycloalkenyl ring moiety; and wherein R.sub.12, R.sub.13, R.sub.14, R.sub.16, R.sub.17, R.sub.28, R.sub.29, R.sub.30 and R.sub.31 represent hydrogen or C.sub.1 C.sub.3 nonadjacent alkyl; wherein s is an integer of from 0 up to 10; t is an integer of from 0 up to 10; and v is an integer of 1 or 2; with the proviso that the sum of s and t is between 0 and 10 according to the inequalities: 0.ltoreq.s+t.ltoreq.10; 0.ltoreq.S.ltoreq.10; and 0.ltoreq.t.ltoreq.10.