caption: The image shows four different types of oysters on a black background with the text "Unio Popei Lea, 1857 USNM 85895" written on them. The oysters are arranged in a symmetrical pattern, with the largest oyster in the center and two smaller oysters surrounding it. The text is written in a bold font and is surrounded by a white border. The background is a deep black color, providing a stark contrast to the oysters and text.