Song-stumper

I thought I'd try a different format for the old stumper feature. Today you'll be filling in the blanks, finishing sentences in this classic song lyric. Actually, it's from some patter that goes between verses of the song. But that's the only hint I'll drop.

As always, if you even think of searching online, you'll not only be disqualified, you'll be racked with guilt for days on end. And before the holidays, you need more guilt like you need another charge on your Amex.
So here we go. Fill in the blanks and name that song!

Not even a rhinoceros? ____(1)_______ How about a hippopotamus? Why, I'd thrash him from top to ______(2)_______! Supposin' you met an elephant? I'd wrap him up in _____(3)_______! What if it were a brontosaurus? I'd show him who was ________(4)_________!