The image is a detailed, black and white biological illustration of a diatom, a type of microscopic algae. The diatom is circular in shape and appears to be viewed under a microscope. Its structure is highly symmetrical, with numerous small, oval-shaped pores or markings arranged in radial patterns emanating from a central point. These pores cover the entire surface of the diatom, creating a textured, almost honeycomb-like appearance. A darker, central line runs vertically through the center of the diatom, adding to its structural definition. The illustration is labeled 'FIG. 5. DIATOM, FROM BORI, HUNGARY. x 1000.', indicating its subject, origin, and magnification level.