This image depicts a dorsal view of a female horse-fly, Tabanus stygius, which had been collected at White Pond, in Sudbury, Massachusetts. T. stygius are very large, dark flies found in mid-summer, biting during the day. Their thorax is whitish, displaying several dark longitudinal lines, while their abdomen is black. They often attack both dogs and humans. This one, in particular, was feeding on the canine pictured in PHIL 15999, when it was captured.