I started my research thinking this fossil was Mahoningoceras Murphy 1974, then later thought it was smashed, had straight flank sutures, and was a Millkoninckioceras Kummel 1963. I reversed this decision again after comparing it to Millkoninckioceras and refocused on Mahoningoceras. Yet, I received a photo of the holotype fromRead More →
The gastropod Bellerophon nodocarinatus (=Euphemites nodocarinatus) was named by Hall in 1858 in a geological report of Iowa. The name means knotty/lumpy kneels (or carina), characterized by the dual lumpy ridges visible from the anterior margin across the shell. Members of Euphemites have spiral lirae that appear in the aperture and extend toward theRead More →
The Vestigastropoda is a subclass of gastropods that live only in marine environments and have a nacreous layer. The group includes members of the superfamily Pleurotomarioidea, known for shells featuring a selenizone. The selenizone is a slit feature on shells that the living creature uses to aim its exhalant current.Read More →
The Earth’s North magnetic pole has long been an essential tool for navigation. Compas needles with one side magnetized always point towards this magnetic pole, and early people thought a magnetic island existed somewhere in the great cold North. William Gilbert (1600, De Magnete) proposed that the Earth acted asRead More →
The brachiopod Isogramma Meek and Worthen (1870) is challenging to identify when found by inexperienced collectors. These fossils appear as a half circle of sharp, equal-spaced concentric growth lines. All specimens appear flattened, making them difficult to identify as dimensional brachiopod shells. The shells are concavo-convex in life, but dueRead More →
The monospecific genus Pennoceras has a limited range, the Brush Creek and Pine Creek limestones in Pennsylvania and Ohio. These curious members of the Goniatitida have a maximum diameter of only 37 mm. Miller and Unklesbay named these from specimens in the Carnegie Museum. My own specimen below is fromRead More →
I’ve been busy writing elsewhere, so the posts portion of this website is starting to age. Nevertheless, I have discovered several new things over the past few months, and I wanted to share at least one. I found a large specimen of a member of the Bellerophontidae, but in theRead More →
In the past, this gastropod was known as Bellerophon (Pharkidonotus). The name in parenthesis is due to subgenera naming. In modern gastropod taxonomy, several sub and super-names are used, including unranked groups that don’t fall into a classic hierarchy. McCoy named the family Bellerophontidae in 1852 in the publication “DescriptionRead More →
Poterioceras curtum is a Pennsylvanian cephalopod first described by Meek & Worthen in 1860. I originally misidentified these as Ctenobactrites isogramma. This is not the first report of this species in Western Pennsylvania. A report from the Annals of the Carnegie Museum in 1947 features specimens from the Brush CreekRead More →
Crosswise cells or rays are typical but often hidden components of the vascular tissue in plans. Fossil plants occur in the shale layers below the Brush Creek limestone. These sometimes preserve incredible detail, including detailed carbon films from plants living over 300 million years ago. While shale plant fossils areRead More →