This report describes a scanning electron microscopic study on the surface of developing tendrils of Parthenocissus tricuspidata Sieb. & Zucc. Epidermal cells of mature branchlets are densely covered with minute corrugations which we shall call microplicae, while the epidermis of immature branchlets is smooth. Epidermal cell surfaces of pads first appear very folded, but develop into a densely packed pattern of hemispheres. When stimulated, heavy exudation of a sticky fluid enables the pad to adhere to a support. Subsequently, epidermal cells nearest the point of contact elongate extensively and divide periclinically, whereas the remaining epidermal cells swell and undergo anticlinal divisions. The adhesive fluid passes through the wall o epidermal cells, accumulates under the cuticle causing the latter to bleb, and is finally exuded from a hole in the cuticular blebs.