Description: With only about a half dozen localities known, trilobites with soft tissue preservation are rare. A well-known site in the United States is Beecher’s Trilobite bed where examples of Triarthrus, Cryptolithus, and Cornuproetus are known. In 2005 a new location in Lewis County was discovered which will take its place in this select group as a site containing Triarthrus eatoni with preserved appendages. This is another location that was found which in addition to Triarthrus has Cryptolithus as well. These trilobites were buried rapidly, resulting in an anxonic environment which allowed for infilling with fine-grained pyritic deposits that preserved the details seen here. The degree of pyritization is less pronounced than that in the Triarthrus. This is a recently-discovered site that is only some 2 meters square, and has Cryptolithus far larger than others seen before. This plate shows numerous graptolites of the species Geniculograptus pygmaeus, the same as what is found at the Beecher’s site.

Graptolites are colonial animals belonging to the hemichordates. The term originates from the patronymic genus Graptolithus. The Graptoloidea were pelagic, drifting with the currents, and were the most important members of the plankton before dying out in the early Devonian. Many were quite cosmopolitan in distribution, and the limited temporal duration of individual species make them excellent index fossils for correlation of strata and biota from widespread locations.