On This Day In Dino-history: September 20, 1953 On This Day In Dino-history: September 20, 1953 On This Day In Dino-history: September 20, 1953 On This Day In Dino-history: September 20, 1953 On This Day In Dino-history: September 20, 1953 On This Day In Dino-history: September 20, 1953