Some cells that are initially part of the epithelial neural tube alter their adhesive properties and disengage from the epithelium to form the neural crest on the upper surface of the neural tube. The cells then migrate away and form a variety of cell types and tissues throughout the embryo. Here they are shown assembling and differentiating to form two collections of nerve cells, called ganglia, in the peripheral nervous system. Other neural crest cells differentiate in the ganglion to become supporting (satellite) cells surrounding the neurons. The crest cells tend to migrate in clusters, and they proliferate rapidly as they migrate.