Tuna Cakes

1/4 cup each chopped green pepper and onions, 1/4 cup mayonaise, 1 tbsp lemon juice, 1/4 tsp salt, 2 5oz. cans tuna drained, 1 egg beaten, 1 cup dry bread crumbs.  Mix all ingredients together.  Roll balls, flatten into cakes.  Fry cakes in melted butter until done.