These byrozoan fossils were brought to me for identification which I could not determine what there genus was. My attention was drawn to several pieces that had either enlarged pores or borings in them. The first picture seems to have circular borings made by a gastropod? Fossils are Orodvician and found south of Lexington Kentucky.
This last picture shows more of raised pores like craters. Is this signs of an infection or different genus? Not sure.
