Cornulitids are filter-feeding worm-like organisms with a hard tube-shaped shell that have been known to encrust hard substrates such as the shells of brachiopods and gastropods from the Ordovician through the Carboniferous. Cornulites proprius is found in the Waldron Shale (Middle Silurian) and frequently are sclerobionts that encrust the platyceratid gastropod Platystoma niagarense. This study looks at the interaction between these two organisms. The cornulitids were counted and categorized into zones representing where on the platyceratid they encrusted. This is analogous to a study done by Morris and Felton (1993) on Ordovician examples. The result showed that the cornulitids encrusted during the life span of the platyceratid. The cornulitids also had no preference on the size of the platyceratid they encrust, and it seems that with age a platyceratid did not accumulate additional cornulitids. Results show that the population of encrusting cornulitids is dominated by juveniles and more than 50% of the population never reached a length greater than 5 millimeters. My hypothesis is that the juvenile population did not live long enough to be affected by the growth of the platyceratid. Yet, there were specimens found measuring less than 5 millimeters that still curved. The results of this study show that the cornulitid behavior was random and the growth of platyceratid shell they were encrusting had no affect on them.


Wilson, Mark




Geology | Paleontology


Platyceratid, Platyceratid gastropods, Cornulitids, Silurian, Secondary Tiering, Encrusters, Sclerobionts

Publication Date


Degree Granted

Bachelor of Arts

Document Type

Senior Independent Study Thesis



© Copyright 2015 Christian P. Tulungen