Sezon 15
Bölümler
1 And God Created Great Whales 9 Eki 1974 2 Children's Hospital 23 Eki 1974 3 The Heimaey Eruption: Iceland 1973 30 Eki 1974 4 Traveller From An Antique Land 6 Kas 1974 5 Mind And Hand 20 Kas 1974 6 Frogs, Snakes and Turtles 4 Ara 1974 7 Discovery on Charlton Island 11 Ara 1974 8 The First Inch 18 Ara 1974