Back when I was in my 20's, I did a time-lapse study of a cactus seedling breaking ground. The seedling was way too small to get the camera close, so I placed a prism adjacent to the erupting seedling and shot vertically downward at the prism. I set the camera on a ring stand and took one or two shots a day. Barrel cactus seedlings are very amusing -- nearly spherical with markings that make it look like a face, the two cotyledons on top are like tiny cat's ears, one of which wears the seed coat, like a beret. That was many years ago, and the film is lost, alas. David E.