Black and white lantern slide of a mastodon bone and measuring grid in an excavated pit at the Jonio Farm site.

Black and white lantern slide of a mastodon bone and measuring grid in an excavated pit at the Jonio Farm site.

Black and white lantern slide copy of a tabulation sheet of the measurements of findings at the Jonio Farm mastodon excavation site.

Black and white lantern slide of a sketch of cross sections of the Jonio Farm site excavation.

Black and white lantern slide of a sketch map showing mastodon bone locations at the Jonio Farm site.

Black and white lantern slide of mastodon bones and measuring stick in an excavated pit at the Jonio Farm.

Black and white lantern slide of the mastodon excavation at the Jonio Farm, a charcoal mass located at point 102.

Black and white lantern slide of the mastodon excavation at the Jonio Farm, with labeled charcoal masses found in the pit.

Black and white lantern slide close up view of a charcoal mass located in the mastodon excavation site at the Jonio Farm.

Black and white lantern slide close up view of a charcoal mass located in the mastodon excavation site at the Jonio Farm.

Black and white lantern slide of several men digging in a marked excavation site on the Jonio Farm.

Black and white lantern slide of farmer John Jonio standing next to a wheelbarrow beside an excavation pit on his farm.

Black and white lantern slide of Robert Merrill and Audie Merrill standing next to a water pump at the Jonio farm.

Black and white lantern slide of a group of around 20 school children gathered around the excavation site at the Jonio farm.

Black and white lantern slide of farmer John Jonio holding two mastodon bones found at his farm.

Black and white lantern slide copy of a map of roads connecting Zion, Bryce Canyon National Parks and Cedar Breaks National Monument.

Black and white lantern slide copy of a geological map of Yellowstone National Park and Yellowstone Forest Reserve from an unknow source.

Black and white lantern slide copy of a sketch cross-section of Amethyst Mountain in Yellowstone National Park, from an unknown source.

Black and white lantern slide copy of a map of a mastodon excavation site in Barry County, Michigan drawn by Robert Hughes.

Black and white lantern slide of several men standing near a ditch and excavation site of a mastodon skeleton in Barry County, Michigan.

Black and white lantern slide of several mastodon bones lined up in front of a hay-filled wagon bed in Barry County, Michigan.

Black and white lantern slide of three women sitting at a picnic in the woods near Croton Lake, Michigan.

Black and white lantern slide of a man standing in a water-filled ditch in which a mammoth tooth was found in Allegan County, Michigan. Several men stand or crouch on higher ground nearby.

Black and white lantern slide of a mammoth tooth from Allegan County, Michigan next to a measuring stick.