Exodus 8:16-19 - Plague Three: Gnats
16 And the LORD said unto Moses, "Say unto Aaron, 'Stretch out thy rod and smite the dust of the land that it may turn to lice in all the land of Egypt.'" 17 And they did so. And Aaron stretched out his hand with his rod and smote the dust of the earth, and it turned to lice both in man and beast, so that all the dust of the land turned to lice, throughout all the land of Egypt. 18 And the enchanters assayed likewise with their enchantments to bring forth lice, but they could not. And the lice were both upon man and beast.
19 Then said the enchanters unto Pharaoh, "It is the finger of God." Neverthelater, Pharaoh's heart was hardened and he regarded them not, as the LORD had said.