Light micrograph of the surface of a moss (Atrichum undulatum) leaf. Two lamellae run along the midrib of the leaf. Also seen are leaf lamina and the toothed margin of the leaf. The red dots in the leaf cells are chloroplasts. Their colour is due to chlorophyll autofluorescence. Observed in ultraviolet (UV) light. Magnification: x160 when printed at 10 x 10 cm.