Immunocytochemical reactions occur in the Crino d: Antedon bifida, in the Asterids: Asterina gibbosa and Asterias rubens.Various antigens (HRP or Horse-radish peroxydase, Alkalin phosphatase) were injected in the animal's coelomic cavity. Animals were "immunized". Observations were done in TEM (Transmission electronic microscopy) by the use of specific labelling and in light microscopy.IN TEM immune labelling were seen in the perinuclear space (EP)...