ABOVE: The carapace of Onychopterella from the Greenfield Formation of southern Ohio.  Specimen preserved in dolostone reportedly of Lockport Age.
Onychopterella kokomoensis, Kokomo Waterlime of Indiana.  The Kokomo is the repository of one of the most significant eurypterid faunas of the world.  Unfortunately, the rock is more coarsely-grained and preservation could be better.
ABOVE: The carapace of Mixopterus multispinosis from the Pittsford Member, lower Vernon Formation, Salina Group at Pittsford, New York. Mixopterus, like the previously described Paracarcinosoma, may have borne a poisonous telson.
AT LEFT: Clintonipterus, presumably a hughmilleriid, known from a single carapace. The speci- men is a plaster cast of a natural cast in sandstone (no integument preserved). The horizon is within the Silurian, either the Medina or Clinton Group, Ontario,County near Lake Ontario.
CIURCA 022069-1, CU 7333.  Thanks to Prof. John Wells, formerly with Cornell University.
Below - A Rare Stylonurid
The Late Devonian of Pennsylvania is providing ample evidence of the presence of stylonurids and interesting associated fauna. The Catskill Delta shed sediments far to the west and nearshore deposits are preserved that contain abundant fossil fish remains and eurypterids.
   Note the crescentric eyes on the well-preserved cara- pace shown to the right. No complete specimen has yet been found, but fragments are abundant. This specimen was found within a sequence of 'Catskill' redbeds.