It ran May 30, 1990, and that entire week's strips were devoted to Jon and Garfield's trip to the veterinarian's office, where Jon repeatedly and unsuccessfully hits on the vet, Liz.

The strip in question shows Jon grabbing a cup on the counter and taking a big swig, apparently in the belief that it's filled with coffee.

"Congratulations, Mr. Arbuckle," says Liz. "You are going to give birth to a fine, healthy litter of puppies."