Planet (The Sabre-Toothed Gorillas)

An Earth-like planet was compared by the Second Doctor to Canada.

The Doctor, John and Gillian encountered a tribe of sabre-toothed gorillas, but were rescued by a a professor who had developed a substance he called squidge. The group used weapons made of squidge to hold off the gorillas until they could make their way back to the TARDIS. (COMIC: The Sabre-Toothed Gorillas)