Figure 6
Reconstruction of Rochester Shale seafloor depositional environment for transitional community type, slightly deeper than shallowest bryozoan thicket assemblages.  Note local patches of Fenestella (far left), Chilotrypa (center) and Hallopora (far right) bryozoan colonies provide attachment substrates for the cystoid Caryocrinites (right); note small coral Favosites parasiticus, attached to the column of specimen on the far right,  and the crinoid Macrostylocrinus (left); note the attached commensal gastropod, Naticonema. Smaller crinoids (Homocrinus) near center of view are attached to small shell fragments. Small solitary rugose corals (Enterolasma), the brachiopods Striispirifer, Atrypa, and Leptaena, and the ophiuroid (brittle star) Protaster, are scattered on the seabed. At the center, the trilobite Dalmanites scuttles along the seafloor and the predatory nautiloid cephalopod Dawsonoceras has captured a platyceratid gastropod. Note burrowing by sediment-feeding worms and a bivalve into the storm deposited, hummocky cross-laminated siltstone in the slice of sediment at base of view. 

Illustration © Emily S. Damstra • www.emilydamstra.com 

This illustration is part of a mural showing three different Silurian environments. The mural is on display at the Giants Rib Discovery Centre in the beautiful Dundas Valley Conservation Area in Southern Ontario, Canada. www.giantsrib.ca

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