Swedish Explorer Johan Gunnar Andersson discovered several of its fossilized branches on Norway's Bear Island in 1899. Remnants of its fanlike leaves have since been found in Alaska. But it remained for Bonn University Paleobotanist Hans-Joachim Schweitzer to determine that an ancient plant called Pseudobornia ursina was actually a tree that grew as high as 65 ft.50 million years earlier than other trees of comparable height are known to have appeared. On a recent expedition to Bear Island, Schweitzer reports in the current issue of the German journal Umschau, he unearthed the first portion of Pseudobornia trunk ever found, a 33-ft. fossilized section composed of bamboo-like segments. It was lodged at the base of a cliff in an Upper Devonian Period stratum some 300 million years old. How it got there is a mystery that Schweitzer hopes to solve on a future expedition, when he will search for Pseudobornia's still-unknown ancestors. "With such a tremendous stature," he says, "it could not have sprung fullblown from the earth."