CREATE TABLE table_23433 ("No. in series" FLOAT, "No. in season" FLOAT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original air date" TEXT, "Production code" TEXT, "U.S. viewers  ( millions ) " TEXT)

How many episodes had the series number of 38?
SELECT COUNT("Directed by") FROM table_23433 WHERE "No. in series" = '38'
SELECT COUNT("Directed by") FROM "table_23433" WHERE "No. in series" = '38'