The image is a detailed illustration of a diatom, specifically identified as 'Navicula lyra'. It's a microscopic organism with a distinctive elongated, oval shape. The diatom's shell (frustule) is intricately patterned with numerous fine, parallel lines running lengthwise. These lines create a textured appearance, and are more densely packed towards the center of the diatom. A darker, central stripe runs along the length of the diatom, emphasizing its symmetry. The edges of the diatom are slightly curved, and the overall appearance is reminiscent of a small, elongated boat or a lyre shape, hence the name 'Navicula lyra'. The illustration is done in a detailed, scientific style, likely from a botanical or biological publication. Below the image, there's text indicating 'FIG. 30. DIATOM, NAVICULA LYRA.' and 'x 900', indicating the magnification level.