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I've been posting Fox Hills Formation fossils from a recent trip but I feel that those are a poor representation of the often spectacular preservation and diversity of the Fox Hills Formation. Because of that I've decided to post some of my better Fox Hills specimens from North Dakota. We'll start with some lovely ammonites. Jeletzkytes nebrascensis is common throughout the Fox Hills Formation in the Timber Lake Member (perhaps a bit less so in North Dakota) and is a typical flagship species for the formation. This microconch from Emmons County is the largest complete J. nebrascensis I've collected. The slash mark is an unfortunate result of removing an ammonite from directly atop this one before I was aware of this one. I think it turned out well despite that.

I had the opportunity to get out to my favorite area of the Fox Hills Formation last week right before the temp skyrocketed into the 100s. I returned to my favorite Timber Lake site as well as tried some new ones. The first site I tried on the way down was not an exposure of the Fox Hills at all but probably of the Cannonball Formation, at least in part. I didn't find anything at this site but it was pretty nonetheless. There's lots of exposed Fox Hills sandstone at my favorite Timber Lake site but the fossils are not as well preserved as those in the concretions. The concretions are often spectacular. This is from the site I describe as Timber Lake Exposure 1 in other threads. I did collect some small concretions pictured later. No large ones but there wasn't much erosion this year due to the dry weather and the lack of snow melt from the mild winter. This new site exposes more of the brackish portion of the Fox Hills Formation. There was tan and salt and pepper sandstone with sparse fossils throughout. The interesting thing was the white-gray claystones and shales exposed at the top of some hills. There were sparse fossils here as well that I took the time to collect just because it is unusual for the area. I haven't prepared anything from it yet. I think most, if not all, specimens were Protocardia subquadrata. I got around to preparing some of the stuff from the Timber Lake exposure. The ammonites in the overlying sandstone layers are typically "pancaked" flat. Typical concretionary material from the site with the abundant wood that is typical of the exposure. Typical immature Scaphitid ammonites. Just a portion of the body chamber. A rather large and robust Cylichna scitula. Aptychus. A swirly crystal Oligopytycha concinna. Ones missing the outer shell are common because of how the outer shell sticks to the concretion. Various other typical specimens are present in the concretions collected but I haven't had the time to prepare them yet. No larger ammonites are likely to be found as the concretions usually split along the plane of the largest ammonites but there may yet be some rarer small specimens present. This particular site has yielded crab fossils, a shark tooth, and many rare mollusc specimens. It's just a matter of finding time to continue preparing the concretions.

I've collected another Fox Hills shark tooth and I wanted to see if anyone more familiar with Maestrichian shark species has any ideas on what it may be. Attached is a preliminary list of species present in the Fox Hills of North Dakota as reported from Hoganson in 1995. There have been additional species discovered since that are present in a recent publication but I don't currently have access to that paper. I do have experience with some of these from other Cretaceous deposits but I welcome input from anyone with ideas. Pictures of the specimen. It has been difficult to get clear pictures due to the size. The incomplete root also complicates things but it is rare enough to warrant a try at identification. The shape and direction of the blade, lack of cusps (it seems complete enough to make this determination) and general stoutness makes me think something along the lines of Paranomotodon but that's just a guess on current information. Labial surface Lingual surface

A few weeks ago we had unseasonably warm weather and I decided to make a trip to central North Dakota and collect from some exposures of the Fox Hills Formation (Cretaceous). I've spent a lot of time in this formation but had some new areas I wanted to try. Views looking up and down on the main cut of a Timber Lake Member exposure. This was the most significant new exposure of the day. Most of the Fox Hills Formation in North Dakota is sandstone of various grain size. The characteristic concretions with fantastic preservation that occur in the type locality also occur in North Dakota, although the concretions at this site were not of that type. Some examples of the concretions of this particular exposure. Some Scaphitidae body chambers are present that were separated from the rest of the ammonite. Not exactly the quality I expect from the Fox Hills Formation.