You can see the surface of a Boston fern (Nephrolepis exaltata) above. This image was taken at high magnification and then cropped to a 1 mm by 1 mm square. Stomata with guard cells are visible on the surface of the leaf as ring-shaped cells. Images: Dylan Wainwright and Marija Gajić (http://bit.ly/2AxryHp).

You can see the surface of a Boston fern (Nephrolepis exaltata) above. This image was taken at high magnification and then cropped to a 1 mm by 1 mm square. Stomata with guard cells are visible on the surface of the leaf as ring-shaped cells. Images: Dylan Wainwright and Marija Gajić (http://bit.ly/2AxryHp).