In medium saucepan, mix 1 1/2 cups applesauce and 3/4 cup water, heat to boiling, stirring. Add 1 - 3 ounce package lime gelatin, and stir until dissolved. Put in refrigerator until slightly thickened, about 1 hour. Stir in 1 1/2 cups cottage cheese, 1/3 cup finely chopped celery, and 1/4 cup mayonnaise. Pour into 8 x 8 inch pan. Cool until firm. Cut into squares and serve over lettuce or crisp salad greens.