Stir together potatoes, scallions, flour, eggs, salt, and pepper.
Heat a film of oil in a deep 12-inch non-stick skillet over moderately high heat until hot but not smoking. Working in batches of 4, spoon 1/8 cup potato mixture per latke into the oil and flatten to 3-inch diameter with a slotted spatula. Reduce heat to moderate and cook until golden, about 1 1/2 minutes on each side. Transfer latkes with spatula to paper towels to drain.