Question: How many Huckleberry Hound episodes were aired on 1960.09.18?
Schema: create table table_19860361_4 (huckleberry_hound varchar, air_date varchar, PRIMARY KEY (huckleberry_hound))
SQL: select count(huckleberry_hound) from table_19860361_4 where air_date = "1960.09.18"