Groucho Marx? ZZZZT, wrong answer.
You're obviously too young to remember Froggie the Gremlin from the old Saturday morning kids radio show back in the 1940s. I never missed that program if we were home with the old Spartan console radio, because Froggie would pluck his magic twanger and tell corny jokes in his gravelly voice that only a kid would think were funny.
OK, so the 1040s were not the ne plus ultra of electronic entertainment, but it was great fun on Saturday mornings if you were 10 years old and no school to dread until Monday.
It was Andy Devine. Jingles.
Groucho Marx? ZZZZT, wrong answer.
Actually I am old enough. I got my shows mixed up. Pluck your magic twanger froggie was from the Buster Brown show, which I used to watch all the time as a kid. Groucho had the duck that dropped down with the magic word. Got my ducks and frogs mixed up. Thanks for catching that for me. Hope Vicomte 13 reads this to know it was from Buster Brown and not Groucho Marx, although I could hear Groucho saying the froggie phrase w/emphasis on sexual innuendo, as he was a bit of a dirty old man.
I remember Saturday matinees for kids at the movies in the 40's, as well as radio favorites such as the Whistler, The Green Hornet, The Saint, The Shadow, The Man Called X & Fibber McGee.