|Cartoon debut||"The Great Sock Mystery"|
Mr. Greenspaniel is a dog that is seen in "The Great Sock Mystery." He explains to Pal exactly how the sock market is important to humans, yet uses terms that Pal cannot understand. He wears glasses and a blue tie, two items that are unusual for the pets in the series to have.
Along with his name, he is a play on Alan Greenspan, the former Chairman of the Federal Reserve. Mr. Greenspaniel's incomprehensible ramblings reference "Fedspeak," the "'turgid dialect of English' used by Federal Reserve Board chairmen in making intentionally wordy, vague, and ambiguous statements" to prevent investors from overreacting to official statements.