where is there a quote referring to symbol of "East vs West" in this chapter?

"From East Egg, then, came the Chester Beckers and the Leeches, and a man named Bunsen, whom I knew at Yale, and Doctor Webster Civet, who was drowned last summer up in Maine....From West Egg came the Poles and the Mulreadys and Cecil Roebuck and Cecil Schoen and Gulick the state senator and Newton Orchid, who controlled Films Par Excellence.."