This is a vintage illustration of a butterfly's tongue, depicted as a long, coiled tube. The tube is tightly wound into a spiral shape, resembling a spring or a coiled hose. The illustration is done in black and white, with fine lines and shading to show the texture and structure of the tongue. The tongue appears to be segmented, with small rings or sections visible along its length. The illustration is labeled 'Fig. 19. Butterfly's Tongue.' and 'x 50.' indicating a magnification of 50x. The background is a cream-colored paper, giving it an antique or scientific illustration appearance. There is text at the bottom of the image that reads 'to face page 80.'