Toby was a dog residing on Earth in the late 50th century. He was the pet of Professor Frederick Marius.
In 4997, Marius was forced to leave Toby behind when he departed for his new posting at the Bi-Al Foundation due to shuttle weight restrictions. He kept Toby's dog tag as a memento. He later gave the dog tag to K9. (PROSE: Tautology)
Behind the scenes[]
According to One Man and His Dog, Marius' dog was named Kelso.