Sept 2016

Strata And Megafossils of the Middle Devonian Silica Formation
Papers on Paleontology No. 8, 1975, reformatted and reprinted, 2012, Robert V. Kesling and Ruth B. Chilman; The University of Michigan Museum of Paleontology; Softcover; 338 pp.

Silica Shale Redux

The book includes a five page Systematic Index (this is hierarchically organized with each entry listing text pages plus plate and figure numbers) plus a table of page numbers for the plates. A valuable table of new edition plate numbers and the corresponding plate numbers in the original version is also included. Four and a half pages of References Cited are provided. Pricing and ordering information can be found at this website: The basic price is $40.00 but shipping options make the final cost vary so refer to the website.

The reprinting of the classic Strata and Megafossils of the Middle Devonian Silica Formation, the “Silica Shale Book,” was a massive undertaking by The Friends of the University of Michigan Museum of Paleontology, usually referred to by the acronym FUMMP or just “The Friends.” FUMMP is a non-profit amateur paleontological group similar to the Dry Dredgers who do considerable work in support of the U of M Museum of Paleontology. The Friends were founded in 1971.

The Foreword provides the story of the direction and timeline of this new version of the famous Silica Shale Book. The roots go back to 2004 when U of M was beginning their digitization project called Big Blue. The Museum of Paleontology decided to keep the original publication out of the Big Blue project to allow The Friends to do a physical reprint. Doing this meant that The Friends could do what they had done for so many years - publish the book and funnel the profits back into support for the Museum.

The Foreword also lays out the specific details of formatting changes, text corrections, reorganization, and photo reproduction. The primary goal was to reproduce a book as true to the original as possible with minimal changes. The tasks were daunting as the original had been done on a typewriter with each page completed as camera ready art. Digitization of the text was accomplished with OCR software and then dealt with in a modern word processor. In order to improve the photo quality to modern standards, the original plates had to be scanned electronically. A nice improvement over the original was made to the Plate captions; a reference is now included for the page where descriptive text can be found concerning the specimens in the photo. A change to glossy paper has also done wonders in improving the photographic image quality.

The impact of all of the changes and improvements has made it difficult to make comparisons between the two editions of the book. To make this easier, The Friends provided a table listing original Plate numbers and the new version’s equivalent Plate number. Since the overall content has not changed, making such comparisons is for the most part unnecessary as users will undoubtedly use the new version exclusively.

There are a couple of obvious questions that need to be addressed, 1) if you already own the original version of Silica Shale Book, why would you want to buy the new version when it is virtually without updates? and 2) of what use is a book whose focus is on a site no longer accessible? We’ll look at these questions one at a time.

For owners of the original 1975 Silica Shale Book, the improvements are significant. The organization has been improved placing everything in a more logical flow. The text references added to the Plates make the book more user friendly as many users first tend to seek a pictorial image to compare to a fossil and then go to the text. The improvement in image quality in the Plates is notably better.

If you’ve never collected the Silica Shale chances are you never will be able to. So why buy this book? This area isn’t the only place that Devonian age fossils can be found so the Silica Shale Book makes an exceptional reference for comparison. Some collectors do their collecting at “Rock Shows” and both Phacops trilobites and Paraspirifer brachiopods from these exposures can be found there. Old collections sometimes show up in the commercial market as well. Besides these more specific reasons, the Silica Shale Book contains a wealth of general information on paleontology, paleobiology, and stratigraphy so it serves as a good way to increase understanding of these topics. Many collectors specialize in a particular kind of fossil such as trilobites, brachiopods or echinoderms. The Silica Shale Book is an easily accessible resource for filling in knowledge gaps for your particular favorite.

The Silica Shale Book begins with introductory chapters that describe the localities, previous research done, detailed stratigraphy and interpretation. Description of localities includes many early photos of the quarry operations as well as locations outside of the classic Toledo area. More site photos and collecting are shown in the detailed section that interprets the stratigraphy. These chapters encompass the first 50 pages of the Silica Shale Book.

The body of this work is almost 200 pages covering the fossil fauna of the Silica Shale in words and photos. The photos are done as they would be for a professional monograph with multiple images per plate. Organization is hierarchical by Phylum: Coelenterata; Bryozoa; Brachiopoda; ?Annelida (Cornulitidae); Annelida; Mollusca; Arthropoda; Echinodermata; and Phylum uncertain. If your only exposure to the Silica Shale has been the Phacops trilobites and the pyritized Paraspirifer bownockeri brachiopods, you’ll be amazed by the other well preserved fauna including the outstanding echinoderms.

The authors reveal the limits they imposed as to what was included and what was omitted. Kessling and Chilman concentrated on the megafauna that was readily identified by a hand lens and thus left out the abundant Ostracods (Ostracods were subsequently presented in Museum publication No. 18 in 1978). They also omitted most of the Bryozoans since, as we know, they typically require thin sections and professional analysis to identify. Kesling and Chilman included tables with each faunal group to illustrate the stratigraphic units where each species could be found; I suppose this would have been most useful in the days when the quarries could be collected directly. Overall, the Silica Shale Book was not intended as a professional treatise but was planned to be amateur friendly.

In a following chapter to the fossil fauna section, Chilman provides a detailed description of the Silica Formation as it appears at the Martin-Marietta quarry. This is a unit by unit breakdown including the dominant fauna found in each.

In a technical and detailed 22 page chapter, David G. Nussmann describes the paleoecology of the Silica Shale unit by unit and lithology by lithology. He also discusses the pyritization seen in some of the fauna. Nussmann’s U of M Master’s Thesis on ecology and pyritization of the Silica Shale fauna was the basis for this chapter.

Kesling contributed a brief chapter, Interrogating the Fossilized Witness, wherein he outlines how paleontologists approach analysis of a fossil. This is an interesting section done in a simplistic fashion to allow for the demonstration of paleontological principles to a non-technical audience.

In an apologetic one page chapter, Osborne B. Nye, Jr (a bryozoan expert from Wayne State University) describes why bryozoans are such difficult creatures to identify.

There are fossil fish remains found in the Silica Shale. Chapter XII By Gerald P. Larson discusses what has been found. Remains appear to be mostly fragmental but specimen photos are augmented by excellent line drawings that help illustrate them.

Chapter XIII by Kesling is a history of the founding of the The Friends of the University of Michigan Museum of Paleontology.

The final chapter is a quiz of sorts for the reader. You can test what you learned from reading this book! This 19 page chapter consists of nine plates, each accompanied by a facing page with a list of questions for the reader to ponder concerning the specimen pictured. For example, questions concerning a brachiopod: “The specimen bears scars of Cornulities. How large was the brachiopod when these parasites first attacked it?” or, “Was the brachiopod alive or dead when the corals grew upon it? Can you be certain?” The purpose here is to illustrate the type of thought processes used by paleontologists when evaluating fossil remains. This is an educational and entertaining chapter to tackle.

Strata And Megafossils of the Middle Devonian Silica Formation is a historically important work on the Midle Devonian Silica Shale that should be of interest to collectors of materials from that locality and for anyone else interested in Devonian fauna anywhere. This is an easy book to recommend. If you have the original version it’s time to put it in your archival library. This new version is better and, since the original has not been digitized and print copies are scarce at best, it represents your only practical way of owning a copy of this classic work.

Readability - Undergrad.
On the Upside - The image quality in this new version is outstanding. The paper quality and printing is much better than the original.
On the Downside - The book was reprinted with minor corrections only; so any changes in taxonomy since 1975 are not included.
Overall Rating - I can highly recommend this book for those interested specifically in this famous Formation and its beautiful fossils. Information contained in Strata And Megafossils of the Middle Devonian Silica Formation is relevant to other Devonian localities as well. The book also contains considerable information that can enhance the understanding of paleontological perspectives and analysis.

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