A shared public role
Contemporary accounts describe dogs called London, Thorn, Toro and Litlon as sharing the Hobo role. Together they show a team-based screen identity, rather than a single unbroken performer history.
What we cannot yet assign
It is not yet clear which dog appeared in a particular episode, scene or publicity image. A shared name alone cannot connect an early performer to a later dog with the same public name.
Future detail
There is still more to learn about individual episodes and performers. This overview introduces the known team without filling those gaps with guesses.