 CONT: When Dana gets out of the cab her groceries include a green  leafy vegetable with a large white stem but when she gets to the  hall it has become completely green lettuce. It changes to celery  while she is talking to Louis. When she sets it on the counter it is  still celery but in the next shot the item on the counter is  lettuce. After the eggs start frying on the countertop it changes to  lettuce and celery each pointing in opposite directions. When  Venkman is checking out the apartment they are both pointing the  same direction.