In the animal world, pigments and colour pigment patterns play an important role. Pigments in the epidermis offer protection against solar radiation, and the various colour patterns provide the animals with concealment, advertisement and disguise (Cott 1940). The study of pigment cells and colour patterns is a multidisciplinary research field which includes developmental biology (determination, differenti- ation, migration), genetics (phenotypic gene expression, colour mutants), cell biology (ultrastructure, organelles, cell surface), biochemistry (enzymes, metabo- lism), physiology (control...