In a bowl stir together the mayonnaise, the parsley, the relish, the onion, the minced celery, the mustard, the lemon juice, the tarragon, the celery seeds, and the Tabasco until the sauce is combined well. (The tartar sauce may be made 1 day in advance and kept covered and chilled.) In a bowl stir together the cod, the eggs, the scallion, the parsley, the onion, the bread crumbs, 2 tablespoons of the tartar sauce, the Tabasco, and salt and pepper to taste, form heaping teaspoons of the mixture into balls, and roll the balls in the ground Saltines. In a large deep skillet heat 1 1/2 inches of the oil to 350°F and in it fry the cod balls in batches for 1 1/2 to 2 minutes on each side, or until they are golden. Transfer the fritters with a slotted spoon as they are fried to paper towels to drain. Serve the fritters warm with the remaining tartar sauce.