Lice. Exodus 8:16. These parasitic insects are still a pest in the Nile valley. Herodotus tells us that the ancient Egyptians peculiarly abhorred such vermin, and were taught by their priests that contact with lice rendered them ceremonially unclean. Some authorities have held that gnats were here intended, but more probably ticks are meant. These ticks are much larger than lice. The body is ordinarily about the size of a small pea; the legs are long, and the creature runs rapidly.