In a medium saucepan cook lima beans and snap peas in a small amount of boiling water for 5 to 8 minutes or until crisp-tender; drain. Rinse with cold water; drain again.
In a medium bowl combine the lima bean mixture, artichoke hearts, dill, and red pepper. Cover and refrigerate for 4 to 24 hours.
To serve, place the romaine leaves in a salad bowl. Spoon the lima bean mixture over romaine leaves. Sprinkle with sliced green onion. If desired, garnish with additional fresh dill and serve with lemon wedges. Makes 5 or 6 servings.