Limnoria spp. are reported as lacking a resident intestinal microflora similar to that found in many other wood ingesting animals (e.g. termites) (Fahrenbach 1959). Instead they are thought to derive their nutritional requirements by assimilation of products produced by the action of endogenous cellulolytic enzymes on wood fragments ingested during burrowing (Ray, Julian 1952). It is however unclear whereLimnoria obtain nitrogen although active feeding on fungal hyphase has been suggested (Seifert 1964). A TEM study of pine wood fragments from the digestive tract ofL. lignorum showed evidence for advanced fungal and bacterial decay indicating ingestion of partially degraded wood.