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Theese are from Evia island Greece an Upper Miocene site with fossils. Any idea what can be the oblong ones ? The cones are freshwater gastropods that can be seen. there is also round and some arced ones. Some have hole in the centre some not . The size also varies a lot from 1 cm to 10 cm
MyGodMagma posted a topic in Fossil IDPhoto: top left Found in a small (10ft wide) woodland stream near the LA/MS border, (East Feliciana Parish, LA/Wilkinson County, MS) within the Citronelle Formation; formed during the Pliostene. While the Citronelle is oft noted to contain fewer saltwater fossils than expected for an ancient coastal plain, this stream has provided probably 95% of the marine fossils in my collection. As a longtime rockhounder but fresh off the boat newbie to fossil identification, I've struggled to find a match for this fossil. (The photo is one I had on hand, am preparing to paint and the fossil is buried in chaos right now.) Betting this ID likely is child's play for most of you, any light you can shine on this fossil would be so very much appreciated. -caroline
a book review of: "The Lost World of Fossil Lake: Snapshots from Deep Time" by Lance Grande. University of Chicago Press. 2013. 425 pages. Suggested retail: $45 USD. If you drive through southwestern Wyoming near the town of Kemmerer during the summer, you encounter the heat and aridity of the high mountain desert environment that has characterized the region since the last ice age. In winter bitter winds contribute to sub-zero temperatures. Local conditions supported very different environments long before the ice ages but one in particular and not so distant in time has captured the attention of scientists, collectors, and interior decorators. "The Lost World of Fossil Lake" examines the 52 million year-old plant and animal remains found in the Fossil Butte Member (FBM) of the Green River Formation. This is the source layer of nearly all those beautifully-articulated "Wyoming fish" we see at mineral shows and flea markets across the country and around the world. The FBM marks the episode of maximum biodiversity within Fossil Lake, a body of water with a life of its own. Paleontologists have been intensely interested in the FBM because it offers evidence of how life recovered after the K/T mass extinction, the event that wiped out the last of the dinosaurs and a variety of other organisms 65 million years ago. The FBM has proven itself to be an extraordinarily rich sample of a freshwater community from microscopic algae to mammals. The author is Dr. Lance Grande, a biologist, paleontologist and curator at the Field Museum. His specialty has been the FBM, and the Green River Formation as a whole, for decades. His publication, "Paleontology of the Green River Formation with a Review of the Fish Fauna," (Grande, 1984) made him more widely known as an authority on the remains of that unit and it became a must-have for collectors of all levels of experience. "The Lost World of Fossil Lake" focuses on FBM organisms with some notes on forms known elsewhere in the formation. The chapters are unnumbered. The first one provides background on the origin of the Green River Lake System, the composition of the Green River Formation, especially the FBM, and the once-living environment now represented by the FBM. The second chapter offers the history of fossil hunting in the FBM, paying tribute to scientists, landowners, land lesses, fossil dealers, and private collectors who have unearthed, studied, or donated rare and significant specimens. The reader also learns about a typical day in a "fish quarry." A short chapter informs the reader on how the fossils are prepared for study and/or display and another shows how organisms are scientifically classified. The next nineteen chapters review the fossils by group sometimes at the level of class (e.g. mammals) and sometimes by convenient grouping (e.g. bacteria). An extra chapter within the review of the fishes offers an informative ranking of species by abundance/rarity which would be of interest to both the researcher and the hobbyist. Before Grande's epilogue in which he leaves the reader with a remaining FBM mystery, he discusses trace fossils that offer clues to the everyday existences of the organisms and the changing conditions of the lake. He brings his book to a close with notes on of what has been learned about the FBM from the study of its fossil content and rock composition. Following the text, a number of appendices provide the reader with faunal lists, a key to FBM localities, and other useful additional information. The text is thorough without being too technical. The reviews of the plants and animals furnish an interesting range of information from the relative abundance of each taxon and its inferred diet/niche to the known fossil and modern relatives and their current distribution. Across the chapters various scientific terms are printed in all capital letters indicating that the term can be found defined in the glossary near the back of the book. This is a very helpful section for anyone who starts looking for technical articles on Green River organisms, because at that level in the literature, a familiarity with those terms will be assumed. This book is abundantly-illustrated and the photos are excellent with some nice close-ups to help the layman understand the details discussed. The selection of photos is not limited to just one or two of each species (unless it is that rare) but also includes samples of growth series (juvenile and adult specimens) of the more common forms. The shots of isolated specimens like fish scales, plant seeds, and coprolites will help the novice recognize what might go otherwise overlooked in the field. Along with all the photos of the well-preserved and expertly-prepared skeletons, I liked the ones exhibiting different levels of skeleton disarticulation found in the deposit with the highest level shown as an apparent explosion of fish scales and bones. It is not a fossil that most people would buy to decorate a living room wall but it is a great illustration of a natural process - what happens when bodies decompose considerably before final burial. It is a visually-striking, non-verbal explanation of why most fossils found are just isolated pieces of the more durable parts of organisms. I could find only minor flaws with this book and a couple of them might be debatable given the goal of the author. On page 213 Grande states that crocodilians appear in the fossil record about 84 million years ago but the group is known to extend back to the Late Triassic or at least 200 million years ago. Even if he was referring to the Eusuchia, or modern-type crocodilians, that group is represented almost back to the beginning of the Cretaceous - at least 130 million years ago. On page 263 he identifies a mammal species, "Palaeosinopa didelphoides, which is known in the FBM by three skeletons...," but later in the same paragraph, he adds "a species determination has not been made for the FBM specimen." He goes from determining the species to saying that the available material has not been identified to that level and he goes from listing three known specimens to reporting that there is only one. These are the kinds of inconsistencies that should have been caught and corrected by an editor. This book works as an identification guide for anyone who has bought or collected his own Green River fossils. However, when Grande reviews the genus Knightia, the most common fish genus in the fauna, he does not provide the anatomical characters that distinguish it from other fishes though he gives a quick tip in separating the two species of Knightia known from the FBM. He does point out the differences between Knightia and Diplomystus in the Diplomystus section. This is a minor inconsistency because the observant beginner can pick up on some generic differences from the specimen photos even when they are not spelled out. In the review of Phareodus, Grande does distinguish it from other genera and lists the features that separate species within that genus While realizing that Grande was focusing on the FBM habitat, I think he could have spent a paragraph describing how it fit into the global landscape. The continents would have been recognizable to modern eyes but with bodies of water in odd places. Even just a paleogeographic map with an explanatory caption would have taught the reader in Australia, France, or China that parts of their countries were also much like southeastern Wyoming in the Early Eocene. Similarly, while he notes that it was a time after the Age of Mammals had started, he could have added that many of today's mammal families had not yet appeared and only the earliest members of many orders were present. The largest mammal of the Early Eocene worldwide was only the size of a dairy cow. Whales and sea cows still had feet. Grande hints at of how far-removed in time the FBM mammals are relative to modern forms with the photos and description of a dog-sized, multi-toed horse and with the special notation marks signifying which of the represented taxa are now-extinct (Perissodactyla is mistakenly notated as extinct on page 260). But, for the benefit of the novice, a little more background would have cemented the understanding that even if Fossil Lake contained a fuller diversity of mammal genera living in the area (as evidenced in Early Eocene fossils found elsewhere in Wyoming), we would not see the remains of forms like squirrels, cats, dogs, bears, skunks, sheep, bison, cattle, or deer because they had not evolved yet (some on other continents). Grande proves himself to be a scientist who can still relate to the child of all ages fascinated by the natural world. He sees the beauty of the fossils as well as the biology. He is very fair in his assessment of the occasionally-strained local relationship between paleontological and commercial interests. Yes, he points out cases of fossil poaching but he also calls out the fruitless government sting that was "Operation Rock Fish." Grande states that his own annual field trips to the area are hosted by a fossil dealer, adding that many of the commercial quarriers have donated a number of significant fossil specimens even when not required to do so. He presents a model situation where both science and business have cooperated to their mutual benefit. "The Lost World of Fossil Lake" retails for $45 but can be found easily for less than $30. That is a cheap price for a 425-page hardback packed with updated information and great photos. I would recommend it to anyone interested in fishes, site-specific books, Eocene fossils, or the Cenozoic Era in general. The FBM was deposited within the warmest five million years of the Cenozoic. Geologists and paleontologists have a special fascination with that time because it was the anticlimactic last gasp of the ancient world, the end the worldwide tropical existence known to the recently-departed dinosaurs. It was just before the Middle Eocene and the beginning of a general cooling trend that would eventually lead to ice at the poles and complex climates in between, the Earth of today. As he notes in his preface, Grande's own childhood interest in fishes and fossils was rekindled in his college years when a friend gave him a "Wyoming fish." In his life he has gone from wanting to know what kind of fish it was to helping other people understand not only that species but also the other known members of that community and their environment. "The Lost World of Fossil Lake" is a low-priced, high-value volume that details one part of the Early Eocene of Wyoming. It could also inspire a student to explore parts of other worlds which had already drifted away from the monsters of the Mesozoic but had yet to be populated by the beasts of our memory. Jess