1997 No. 52 Part 1 - Bedfordshire Natural History Society

Bedfordshire Naturalist for 1997, No. 52 (Part 1) (1998)
dogger was carefully .split into a number oflarge but manageable fragments weighing
in total approximately 60kg which were then transported by dumper vehicle to the site
office and the writer's car, a distance ofsome 1000 metres.
Much to the Recorder's and Dr Casey's disappointment there proved to be no
evidence ofan ammonite fauna within this particular dogger. Nevertheless, an
interesting though small assemblage offossils occurred in the hard phosphatic matrix
and the structure ofthe·dogger itselfwas unusual, not being solid throughout but
having an ovoid core ofsoft white marly sand rougWy 200mm x 150mm in size. This
soft core was encased in an extremely hard, dark grey phosphatic matrix rendered very
brittle by numerous clusters ofnarrow; irregularly contorted serpulid worm tubes, each
tube being lmm or less in diameter and with up to fifty or sixty tubes in each cluster.
A small example was determined by Paul Jefferey ofthe Natural History Museum
Dept. ofPalaeontology as Sarcinella plexus (T. de C. Sowerby) the individual tubes,
however, being narrower than in the Museum material.
Preservation ofthe clusters, which extended throughout the dogger, was exceptionally
good due to the hardness ofthe matrix and several larger specimens were· later donated
to the NHM collection. A typical example from the Clophill assemblage is shown in
IOmm
Figure 2. Clustered, irregularly contorted tubes ofthe serpulid worm Sarcinella plexus G. de C.
Sowerby) in fragment ofthe large phosphatic dogger shown in Figure 1.
Upper Aptian Parahoplites nuifieldiensis Zone, Clophill Fuller's Earth quarry (Beds 5 and 6). 4 July
1997.
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