Ciliated cells on the surface of embryos of Scyliorhinus canicula

Monociliated surface cells were found for the first time in an elasmobranch and were common on embryos of Scyliorhinus canicula. They occurred mainly near the anterior end, until Ballard stage 30, but disappeared soon thereafter. The functions of surface ciliated cells suggested in other embryos (e.g. surface currents in lungfishes and amphibians, and determination of left–right patterns in amniotes) seem unlikely in elasmobranchs.