The Big Sneeze/Go to Sleep Wartz (#116)
Bob is allergic to a bouquet of flowers.
Edit: From another site - The Big Sneeze: When Burdette brings Bob a bouquet of flowers, Bob starts sneezing and can't stop until he learns from Madge what an allergy is and that he must be allergic to the flowers. Everything works out when Bob realizes that he can give the flowers to the ants as a present.
Note: Bob is an anteater puppet.