Complex sentence: No correlation of fungal bioluminescence with cell structure has been found: it may occur in both mycelia and fruit bodies--as in "Panellus stipticus" and "Omphalotus olearius"--or only in mycelia and young rhizomorphs--as in "Armillaria mellea".
Split into simpler sentences: No correlation of fungal bioluminescence with cell structure has been found. Bioluminescence may occur in both mycelia and fruit bodies, as in "Panellus stipticus" and "Omphalotus olearius", or only in mycelia and young rhizomorphs, as in "Armillaria mellea".