The extinct cephalopod Metacoceras clinocostatum is a species commonly found in Brush Creek limestone. Compared to other examples of the genus Metacoceras, it is very small in size. I was apprehensive about identifying these. In the past, I believed they were the inner whorls of larger specimens. But, these are
Without a doubt, the genus Metacoceras is one of the two most common cephalopod genera found locally. This particular specimen preserves inner chambers. It did split in half while I was recovering it, but to my surprise, everything remained intact. Individual septal wall/suture lines can be seen on close inspection.