Light micrograph of skin epidermis and dermis in cross section. The epidermis is the outermost layer of skin composed of squamous cells (purple). The dermis is the layer beneath the epidermis, and consists of collagen fibres (pink) containing blood vessels (small white spaces) and skin adnexal structures. The dermis protrudes into the epidermis in structures called papillae. By taking a horizontal cross section through the skin, the dermal papillae look like roughly circular structures in between the epidermal cell layer. Haematoxylin and eosin stained tissue section. Magnification: x200 when printed at 10cm.