ABSTRACT
In this paper, the morphological development of periderm of the hands and feet of 21 human embryos were investigated. The estimated gestational age (EGA) of the collected specimens were 6-24 weeks.On 36th to 41st days of EGA, the cells of embryonic periderm were seen to be flat and polygonal in shape. Microvilli were seen on the cell surface. At the end of 7th week the cells showed conspicuous central elevations as cobblestones. After 11th week, a large single bleb occurring on the cell surface were observed. At 4th month, the number of the blebs increased and complex blebs were formed. Larger blebs showed infoldings and furrows. Then the blebs disappeared and the cell surface became flat again. The cells of periderm began to shed at 17th week.The development of periderm on the hands appeared earlier than that on the feet. The degree of the development of periderm in different regions of hands and feet may be different. The possible significance of the periderm was discussed.