Alfred Nicholson Leeds and the first fossil egg attributed to a ‘saurian’

Abstract

Discovered by the nineteenth century collector Alfred Nicholson Leeds, the first object to be described (1898) as a fossil reptile egg is a unique find from the Oxford Clay near Peterborough. It also comes from one of a very small number of Jurassic localities worldwide that can claim to have yielded a fossil egg. Given its historical and contemporary significance, this object is reassessed in the light of increased understanding of such objects. Data from scanning electron microscopy, computerised tomography, synchrotron imaging, X-ray diffraction and petrographic thin sectioning prove inconclusive. However, the presence of apparent external openings resembling angusticanaliculate pores – a pore type common only to certain types of dinosaur eggshell – in both size and sparseness of distribution prevents its summary dismissal as not being a dinosaurian egg.

Keywords::

• Alfred Nicholson Leeds
• dinosaur egg
• Oxford Clay
• Callovian

Acknowledgements

The authors thank both reviewers for much assistance in improving the text, Frankie Jackson and Colin Shaw (Figure 7(b),(c)), Montana State University, for providing thin-section images; Gordon Cressey and Peter Tandy, Department of Earth Sciences (Mineralogy), NHM, London, for the XRD analysis (Figure 4); Tony Wighton, NHM, London, for thin sections (Figure 7(a)); Phil Crabb, Photographic Studio, NHM, London for images of the Leeds egg; Vincent Fernandez for SYNCHROTRON access; Steve Baker, Department of Earth Sciences (Palaeontology), NHM, London, for providing access to the collections and help identifying the ammonite; Kirsty Ross, Senior Radiographer at the Western Infirmary and Vale of Leven Hospitals (Glasgow), for her infinite patience in steadfastly piloting CT scanners through the weird fossil remains that JJL has for far too many years been bringing her; Caroline Smith and Martin Lee (Figure 6(a)) for steering the Lo-Vac SEM in the University of Glasgow's Gregory Building; Bobby Davey for processing the DICOM scans into ‘glorious Technicolor’ using the Voxar 3D software package; Bob Nicholls for fantastic eleventh hour ‘Pteroportation’ work at www.paleocreations.com; Ian Rolfe for selflessly transporting a fossil egg from London to Glasgow, and Eric Buffetaut for doing the same from London to Grenoble and Cambridge; and Paul Taylor and Alex Brown (NHM) for taking SEMs (Figure 6(b),(c)) and discussion. We also thank Neil Landman and Al McGowan for helpful molluscan assistance. Mike A. Taylor suggested the rotting maternal corpse as a means of facilitating egg recruitment into the marine realm.