I hope that if you are reading this you will enjoy the song too, and learn how to sing it at a moment's notice. It was written for Groucho Marx, that genius comic of the 20th century, and is performed here by himself and cast, in the movie At The Circus (1939).
The song's intricate lyrics are hilarious:
Lydia oh Lydia, that encyclopidia,
Oh Lydia the Queen of Tattoo,
On her back is the Battle of Waterloo,
Beside it the wreck of the Hesperus, too.
In this clip, Groucho Marx looks like he could be 17, even with that moustache, and he also looks as if he is enjoying himself very much. It's also funny to hear the joke he slips in while telling how he first met Lydia: "...at the world's fair in 1900... marked down from 1940."
As the song goes, "You can learn a lot from Lydia," and listen to Groucho's classic Noo Yawk accent, where even in the word 'learn', he tries very hard not pronounce the letter 'r'.