Culture Vulture (Emily Post?)

[Bapopik at AOL.COM]

     "I can tell when you're lying--your lips are moving" and its variants
has been traced to the 1940s, but my guess is that it was born in 1937 or
1938, by Edgar Bergen and Charlie McCarthy.
     I didn't find the joke in the few articles I read, but I did find this
Charlie McCarthy line, in THE READER'S DIGEST, March 1941, pg. 16, col. 1:

     Presented to Emily Post, he called her "a vulture for culture"...

     The Museum of Broadcasting in New York might have the NBC radio
program--the shows are indexed by date and guest.