The Jurassic Flora of Yorkshire

by J.H.A. van Konijnenburg-van Cittert and H.S. Morgans

Palaeontological Association, 1999, 134 p.
ISBN 0-901702-64-1; $24.00 U.S. or £ 12 U.K.

With each generation of paleobotanists, new tools, new methods, and new paradigms guide research. Now more than ever before, paleobotanists are conducting research and collecting data not only on plant anatomy and morphology, but also on the sedimentology, facies architecture, and stratigraphic context of the fossil deposits. All of this information, combined with the recognition and documentation of compositional variation on both small spatial and temporal scales, has permitted more accurate reconstructions of the paleoecology of the source vegetation. Although applied to new localities, “classic” localities often go un-restudied in light of the new paradigms, despite their importance.

The plant-bearing beds in the Middle Jurassic Ravenscar Group of Yorkshire have been investigated for more than a century and the 250+ species from over 600 beds have been described in numerous publications, notably in Harris’ five volume set ( Harris 1961, 1964, 1969, 1979; Harris et al. 1974). The authors of this field guide have selected four plant beds (Hasty Bank, Hayburn Wicke, Gristhorpe, and Scalby Ness) and provided descriptions, photographs, and keys to over 100 of the most commonly found species in these beds.

The text is concise, without flourish, but with enough detail to characterize and differentiate among the many taxa. Numerous line drawings are used to clarify morphological features described in the text and a glossary is provided for morphological terms employed in the descriptions (one exception is “falcate: curving forward” which otherwise is defined within the text). Without material in front of me, I usually find keys impossible to read, but those provided are simple and straightforward. The most important part of any guide to fossils is the photographs. The photographs are abundant, with most species illustrated by at least one image. The photographs are large enough and generally have sufficient contrast to show the necessary details clearly.

Errors in the text are extremely few—I counted only five. Two are related to figure referrals: Osmundopsis sturii is referred to in text as Text-Fig. 17C, but is 17D (p.41); and Czekanowskia microphylla is referred to in the text as Text-Fig.42C, but is 39C (p.107). The others are even more minor.

If there is great value to this guide beyond the taxonomic descriptions and images, and I believe there clearly is, it lies in the addition of detailed stratigraphic sections that describe the lithologies, sedimentary features, and facies interpretation that provide important and often neglected context information for collectors – both amateur and professional. Anyone approaching these beds will be prepared for what they will encounter, not only in terms of the plants, but also the geology. The authors also provide a very informative table that describes the distribution and relative abundance of each plant species in each plant bed. Finally the authors conclude their guide with a discussion of the paleoecology of the Ravenscar Group and the Yorkshire plant fossil beds. The integration of plant distributions and facies characteristics to form a classification system of the deposits provides an informative synthesis of the nature and deposition of the original vegetation. In view of that synthesis, if there is one thing missing from this guide, it is illustrations of plant reconstructions. I realize that few have been completed, and I can hardly fault the authors for their absence, but I can wish it otherwise.

The authors are to be commended for compiling a clear and instructive introduction to the fossil floras of the Yorkshire Jurassic for collecting novices and veterans. Having completed this review, I am compelled to point out that I have never been to these localities. But with this guidebook, with the pictures, keys, maps, and stratigraphic sections it contains, I am sure that I could easily locate these plant beds and identify most of the fossils I collect. I hope one day to give this guide a true test. 

Copyright: Palaeontologia Electronica, 15 April 2000