'Darting' in the Bible

"Don't rejoice, all of you Philistines, that the rod that struck you is broken, because from the snake's root a viper will spring up, and its offspring will be a darting, poisonous serpent.

An oracle about the animals of the Negev: "Through a land of trouble, dryness, and distress, of lionesses and roaring lions, where there is no water, a land of vipers and darting snakes, he carries their riches on donkeys' backs, and their treasures on the humps of camels, to a nation that cannot benefit them,