Article: Ammonoidea from the Lower D beds (Berriasian) of the Speeton Clay
The subdivision of the Lower D Beds is outlined and ammonites are shown to occur at nine horizons in D6 and D7. The ten species of ammonites fall into four genera and have links with faunas found in Lincolnshire, Russia, and Greenland. Four existing species are recorded, three are compared or have affinities wilt existing species, and three species are new. It is shown that this fauna is of Subcraspeditan (Berriasian) age and that the lowest ammonites are earlier than any yet recovered from the Spilsby Sandstone of Lincolnshire.