Non-phloroglucinol lipophilic compounds of the glandular excrete of Dryopteris assirnilis S. WALKER have been analyzed from the internal glandular hairs of the rhizome. A relationship between the compounds identified and the lipid droplets visible in electron micrographs of the glandular cytoplast is proposed.

Evidences based on feeding experiments and electron microscopic studies are presented to support the hypothesis that methylation is involved in the biosynthetic formation of the higher acyl side chains in the Dryopteris phloroglucinol derivatives.

The occurrence of various hydrocarbon, fatty acid and terpenoid constituents in glandular cells in the rhizomes of three Dryopteris fern species has been evaluated by statistical treatment of quantitative data from gas chromatographic analysis. The results obtained suggest complicated interrelationships, presumably resulting from the excretion process, between representatives of the three types of compounds. The species investigated show differences as to these interrelationships.

The structure of internal glands in the rhizomes of Dryopteris assirnilis S. WALKER is investigated by electron microscopy. The anthelmintically active phloroglucinol derivatives are biosynthesized in the glandular cytoplast and subsequently excreted through the plasmalemma and the cell wall to be accumulated under the cuticle as constituents of a subcuticular excretion layer. Some of the final reaction steps in the biosythesis of these compounds are possibly associated with the excretion process.