'Serpent's' in the Bible

I went out at night through the Valley Gate toward the Serpent’s Well and the Dung Gate, and I inspected the walls of Jerusalem that had been broken down and its gates that had been destroyed by fire.

The wolf and the lamb will feed together,and the lion will eat straw like the ox,but the serpent’s food will be dust!They will not do what is evil or destroyon My entire holy mountain,”says the Lord.