Featured in this lot is this Montana Petrified bison occidentalis. The skull is excellently preserved and shows elongated horns and bulging eye sockets, common of the bison occidentalis. This bison occidentalis was a species of bison that inhabited North America from 5000 to 10000 years ago. Evidence shows that the Great American Buffalo we know today evolved from the occidentalis around 5000 years ago. The condition of this petrified skull is fair, with the lower jaw and nasal cavity missing. The measurements of this occidentalis skull are 16 1/2" x 22 1/4" x 8 1/2".