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One of the rock clubs I belong to decided to go on a geode hunt near Keokuk, Iowa. Our private hunting area was not accessible due to flash flooding that previous evening, so we went to another dig site. A good 20 inches of goopy muck unfortunately overlayed the rock that contained the geodes. So I was hot and exhausted by the time bedrock was found. For fear of heat exhaustion, I quit at about 3/4ths of a bucket full. I will take these to the children's fossil pit for the kids to "find". Here is what the collecting site looked like., a split slab showing some geodes surrounded by MUD! With geodes in hand, or at least in the back of my truck, off I went to collect some Burlington Limestone that contained fish teeth. Permission was granted from a quarry known to expose the layer needed. Once the correct "pile" was located, I quickly put about 50 pounds of matrix containing the teeth in with the geodes. This matrix will painstakingly be broken down this winter in order to extract the teeth. Here is some of the material collected showing how rich the rock is in fish pieces. All of the black specks are fish remnants. While loading the truck, mother nature was beginning to expose a mayfly hatch. No mayflies were present when I arrived, but a short time later, the hatch began. I had multiple routes available to take home and decided on one that took me through some Pennsylvanian strata. This would be new territory and hopefully interesting material for me to explore. An old mining operation near Oskaloosa, Iowa was converted into the Russell Wildlife Refuge. There are 5 mine pits on the property exposing the mississippian Pella Formation. I chose this site because it contains blastoids. Unfortunately, the blastoids evaded me. But plenty of new fossils were found!!!!!!!! Brachiopods were the predominant fossil found, but some bivalves, crinoids, gastropods, and bryozoans showed up. Brachiopod ID was difficult due to the lack of much information. I tried my best and am open to changing the identity of anything labeled or adding a name to the unknowns. The rugosa coral has a beautiful appearance and is know for the protrusions on its surface. Most fossils found needed very little cleaning and are presented as shown like these corals. All fossils found are on the small side, That is why this burrow surprised me. I wonder what "large" animal existed in this environment. I have always had an affinity for epibionts. And they were plentiful here! As mentioned earlier, this site is known for blastoids. But the other unique feature is the presence of crinoid stems with bryozoan epibionts. This was a fun spot to hunt and recommend it for a great variety of Pennsylvanian fossils!!! Mike

Does anyone know of a good (or even not so good) reference for Pella Formation fossil identification? My searches have proven mostly unsuccessful! Mike

Fossil Plants From Cave Deposits, Near Pella, Marion County, Iowa lepidostrobus Sp. Brongniart- arborescent, 310 Mya old, Club Moss locality, Pella, Iowa Formation, Pella Beds Age Pennsylvanian The Lepidostrobus is the generic name for the cones of arboresent lycopsid. It corresponds closely in structure with the fertile spike of the living Selaginella. The spore-bearing leaves are attached to a central axis in a crowded spiral arrangement, and their outer ends curve over so as to form an imbricated, diagonally arranged pattern, resembling that of the stem itself. The Lepidostrobus cones produced spores and megaspores.

Omphalophloios Sp. Lesquereux Pennsylvanian Arborescent, 310 Mya old, Pella Beds, Pella, Iowa Omphalophloios is a genus of fossil lycopsid trees in the Carboniferous system.