CREATE TABLE table_31501 ("Townland" TEXT, "Area (  acres  ) " FLOAT, "Barony" TEXT, "Civil parish" TEXT, "Poor law union" TEXT)

which cilvil parishes have areas of 405?
SELECT "Civil parish" FROM table_31501 WHERE "Area( acres )" = '405'
SELECT "Civil parish" FROM "table_31501" WHERE "Area( acres )" = '405'