Sometime back in the 1980's I subscribed for a year or so to the Magazine of Fantasy and Science Fiction. During that period of time I read a short-story (probably in this magazine, but possibly elsewhere) which involved a person who was able to see a different landscape than the one which is currently present—able to see different plants and animals than are currently living. I think that the people in the story worked out which geologic period (s?)he was seeing by comparing the descriptions of what was seen with a geologic map. Alas, I read that story before taking my first geology class. Now that I am a geologist, I would love to go back and read it again. However, I have no idea what it was called, who wrote it, or even if the geology part was a minor interesting side part of the story, or the overriding plot device. Do any of you remember reading this story?