The fauna of the Horseshoe Canyon Formation is well-known, as vertebrate fossils, including those of dinosaurs, are quite common.
Gilmore led sixteen expeditions to collect vertebrate fossils during his tenure as Curator.
Jepsen (1930), "New vertebrate fossils from the lower Eocene of the Bighorn Basin, Wyoming".
Although they knew the find was important they both knew collecting vertebrate fossils on public land was a crime.
Many vertebrate fossils have been found from the formation, including those of cartilaginous fishes and unusual Triassic reptiles like Sharovipteryx and Longisquama.
The unit contains calcareous nodules of varying sizes as well as poorly indurated "conglomerate" with vertebrate fossils.
Contrary to your article, anyone lacking a permit is prohibited from collecting vertebrate fossils from public lands.
That distinction goes to a group of medium-size monkeys, colobines, which accounted for more than 30 percent of all vertebrate fossils found.
Nine sites have been discovered with predominately vertebrate fossils, invertebrates and plants being less represented.
Many vertebrate fossils proved to be present in it.