CREATE TABLE table_55368 ("Title" TEXT, "Original story author" TEXT, "Director" TEXT, "Original U.S. air-date" TEXT, "Original Canadian air-date" TEXT)

What was the Original Canadian air-date for the episode directed by mark rydell?
SELECT "Original Canadian air-date" FROM table_55368 WHERE "Director" = 'mark rydell'
SELECT "Original Canadian air-date" FROM "table_55368" WHERE "Director" = 'mark rydell'