Fossil specimen of the bryozoan *Spatiopora corticans* encrusting the shell of a straight-shelled cephalopod; specimen is from the Ordovician Waynesville Formation of Butler County, Ohio. Specimen is from the collections of the [Paleontological Research Institution](http://www.priweb.org), Ithaca, New York. Specimen is approximately 8 cm in length. Model by Emily Hauf.