The gills of Lepidosiren are very much reduced, consisting of a few lobe-like filaments. The gill epithelium differs from most other fish in being 4–7 layers thick. Three varieties of cell are described which occur in the inner epithelial layers. It is suggested that these represent stages in the synthesis of a granular secretory product. The superficial cells show characteristics of all 3 cell varieties, the granules apparently being voided into the microvillar pits at the surface. Surface cells are joined by junctional complexes typical of fish epithelia. Epithelial cells are separated by interstitial channels which are bridged by long cytoplasmic processes united by prominent desmosomes.