The general structure of the skin of the Lesser octopus, Eledone cirrhosa is described. The component regions and cell types being (1) the epidermis, composed of columnar cells with a border of microvilli on their external surface, mucous cells and secretory cells of an unknown type, abutting a non cellular basal lamina; (2) the dermis, containing the elements of the colour change system, vascular and neural processes and an a cellular matrix.
A sequential, morphological study of wound closure revealed three major mechanisms in the healing response; muscular contraction, a dermal cellular reaction and epidermal migration. The process of wound closure in Eledone is significantly slower than that seen, for example, in teleost fish (30 h rather than 30 min for the initiation of epidermal migration). The significance of these results in relation to the osmotic balance between seawater and the internal milieu of Eledone is discussed, together with their relevance to resistance against infection by pathogens.