During the 1950s, Professor John Cowie was one of a team of scientists who mapped the geology of Greenland. They spent several field seasons on the island, travelling by dog-sled and enduring severe Arctic conditions. Cowie and his colleague Adams studied rocks in Central East Greenland, producing a landmark monograph on the geology. They concentrated on mapping and determining the ages of the various rock formations, and did not discuss the fossils they collected in any detail. Following his retirement, Professor Cowie donated his collection of Greenland fossils to the National Museum of Wales, mainly trilobites of Lower Ordovician age (490-470 million years old). Trilobites of this age from Greenland have not been studied since the 1930s, so work is in progress to describe and identify the Cowie Collection fossils. Research so far has revealed several new trilobite species. Most of these trilobites would have lived on shallow water reefs.