In a bowl whisk together horseradish, mustard, vinegar, paprika, salt, and cayenne and add 1/3 cup of oil in a stream, whisking until emulsified. Stir in scallions and celery. Remoulade may be made 1 day ahead and kept chilled, covered. In a bowl dredge crawfish in seasoned flour and shake in a sieve to remove excess flour. In a kettle heat 1 1/2 inches of additional oil to 390#F. on a deep-fat thermometer and fry crawfish 4 batches 45 seconds, or until golden. Transfer crawfish with a slotted spoon to paper towels to drain. In a bowl toss together romaine and radicchio and divide among 6 plates. Arrange crawfish on lettuce and serve with remoulade. Serves 6 as a first course. Gourmet May 1994 Posted to recipelu-digest Volume 01 Number 185 by jecraig@lan-inc.com on Oct 31, 9