I lied. I went back & checked. It's in 'Talk to the Animals' (or rather, it isn't). What I was half-remembering was:
Quote:
If people asked us, can you speak in rhinoceros, We'd say, "Of courserous, can't you?"
source:
https://www.lyricsondemand.com/d/drdoolittlelyrics/ificouldtalktotheanimalslyrics.html