In 1835, Dexter Marsh, a local laborer, was busy at work quarrying slabs of stone for a sidewalk in Greenfield when he noticed something in the stone that piqued his interest: tiny depressions that appeared to be the tracks of large birds. He was wrong; what he had found were the first dinosaur tracks to be found in North America. In the 1908 annual meeting minutes of the Pocumtuck Valley Memorial Association, Dexter Marsh is remembered as a man who was unassuming and not formally educated, but hard-working, highly skilled, and of endless capacity for exploring and excavating dinosaur fossils. At the time of his death in 1853, his collection included  over 700 fossils, and he had supplied more to institutions across America and Europe. We have photos of Dexter Marsh and a sampling of his dinosaur tracks.