Pyramidal cells are the majority class of cells in the neocortex. They have high density of dendritic spines, prominent apical dendrites, and axons that project out of the cortex as well as locally within it. Soma for these appear in all layers except I. Spiny stellate cells are distinguished from pyramidal cells here by the absence of the apical dendrite and the fact that their axons also do not leave the cortex. These cells are thought to begin as pyramidal neurons and then retract their apical dendrites and axons.