"Then, we tried to remove the tusks, ... but they were embedded in so firmly, we couldn't budge them. Of course, in Alabama the Tusk-a-loosa. But that's entirely ir-elephant to what I was talking about." [Similar to a joke Chico would later tell in Duck Soup]
"Africa is God's country – and He can have it."
"We took some pictures of the native girls, but they weren't developed. But we're going back again in a couple of weeks!"
Kind of an obscure Visual Pun, but when Chandler offers the Professor and Ravelli a check, and Ravelli asks the Professor to see if the check is good, he drops it to the floor and it bounces back into his hands. Maybe it was because this troper was Late to the Punchline, not understanding when he first saw the movie what a "bounced check" was...