The Ammonite Review

 How the review works

The aim of the review is to establish material that is of scientific merit and specimens which are good representatives, possessing public potential for display and community events. These two criteria do not necessarily go hand in hand; as a specimen may have a fantastic scientific research potential, but may not be visually impressive. Therefore the specimens are graded against two separate criteria: Scientific Merit (as a numerical value of stars) and Public Engagement (as a Gold, Silver or Bronze status).

For a more in depth look into the review criteria, click on the “Review Criteria” tab in the tool bar above.

 

The Ammonite Review

 

The Ammonite review is more of a title, as it covered 804 specimens of Ammonites, Coleoids (octopus, cuttlefish, squid) and Nautiloids over 45 trays; alas Belemnites were not covered.

The collection contains specimens from a number of historic SSSI sites, predominantly from the local region of North Yorkshire and the Southern England localities in Somerset, Gloucestershire, Wiltshire, Kent and Dorset. The collection also has a few additional European localities from France, Austria and Germany (Solnhofen). The bulk of the collection are Jurassic specimens with some Carboniferous and Cretaceous material, and are stored in the archives at the Discovery Centre, with some specimens on display at Leeds City Museum. For a detailed analysis, please read Robert’s summary that the end of this review.

Making a start on a third of the collection.

 

Robert Chandler led the 3 day review in a systematic, tray by tray investigation, often insitu in the store, which resulted in the discovery of some incredible specimens. Rather than give a day-by-day account as in previous reviews; the results of this review will occur as an overview with some of the highlights.

 

 

The Gold specimens

 

Leedm.B.1979.15.293

A wonderful Jurassic Parkinsonia rarecostata (3 Gold stars – Leedm.B.1979.15.293) specimen from Crewkerne station, Somerset, England; part of the Buckman collection.

 

Leedm.B.1979.15.211

A very good Jurassic Witchellia laevisulca (3 Gold stars – Leedm.B.1979.15.211) specimen from Dundry hill, Bristol, England; part of the Buckman collection.

 

Leedm.B.TN4786 & Leedm.B.2009.005

A rare and extinct species of Jurassic cuttlefish Loligosepia bollensis (3 Gold stars – Leedm.B.2009.005 & Leedm.B.TN4786) featuring soft body and ink sack preservation, with incredible tentacle hooks (detailed below). From Lyme Regis, Dorset, England. Colour difference due to specimen display past.

(Detail of Cuttlefish body) Leedm.B.TN4786

(Detail of tentacle hooks) Leedm.B.2009.005

 

 

Leedm.B.1979.15.6

A wonderful Jurassic Brasilia bradfordensis (3 Gold stars – Leedm.B.1979.15.6) specimen, rare for its location of Stoke Nappe, Dorset, England; part of the Buckman collection.

 

Leedm.B.1979.15.53

A striking Jurassic Radstockiceras sp.  (3 Gold stars – Leedm.B.1979.15.53) specimen from Frome, Somerset, England; part of the Buckman collection.

 

Leedm.B.1979.15.19

A very interesting Jurassic Pavlovia sp. (2 Gold stars – Leedm.B.1979.15.19) specimen, an inner whorl of a larger ammonite with an abrupt change in shell morphology (below) – evidence of surviving predation. From Hartwell, Oxfordshire, England.

(view highlighting the change in morphology) Leedm.B.1979.15.19

 

 

Leedm.B.1979.15.47

A striking and rare Jurassic Bechiceras sp. (2 Gold stars – Leedm.B.1979.15.47) specimen from Napton, Warwickshire, England.

 

Leedm.B.1979.15.14

A wonderful Jurassic Spinikosmoceras sp. (2 Gold stars – Leedm.B.1979.15.4) specimen (male – microconch), compressed with very good preservation and clearly defined lappet.  From Chippenham, Wiltshire, England.

 

Leedm.B.1979.15.228

An interesting  Jurassic Harpoceras sp. (2 Gold stars – Leedm.B.1979.15.228) specimen with unusual shell pathology, as regular indentations on both sides of the phragmocone;  indicating predation recovery. From Stockton Hill, near Napton, Warwickshire, England.

 

Leedm.B.1979.15.117

A rare and historically cut Parkinsonia dorsetensis (2 Gold stars – Leedm.B.1979.15.117) specimen with underside featuring mudstone and mineral infill (pictured below); from Neather Compton, Dorset, England.

(cut & polished underside) Leedm.B.1979.15.117

 

Leedm.B.1979.15.123

A very good Jurassic Liparoceras sp. (2 Gold stars – Leedm.B.1979.15.123) specimen with unusual and striking preservation; from Warwickshire, England.

Leedm.B.2014.05.780

An interesting and beautifully preserved Cretaceous heteromorph ammonite Hamites sp. (1 Gold star – Leedm.B.2014.05.780) specimen with additional bivalves in the matrix. From Folkstone, Kent, England.

 

Leedm.B.2015.05.485

A wonderful historically cut, unidentified Jurassic Nautilus sp. (1 Gold star – Leedm.B.2015.05.485) with mudstone infill chambers exhibiting beautiful mineralisation  (pictured below). From Whitby, North Yorkshire, England.

(cut & polished underside) Leedm.2015.05.485

 

 

Leedm.B.1990.01.4095

An interesting Carboniferous Goniatite specimen Gastrioceras carbonarium (0 Gold stars – Leedm.B.1990.01.4095) with no locality data.

 

 

The Silver specimens

 

Leedm.B.1974.15.28

A truly wonderful Jurassic specimen, featuring numerous Arnioceras semicostatum (2 Silver stars – Leedm.B.1974.15.28) ammonites and gastropods, in a rare burial assemblage. From Whitby, North Yorkshire, England.

 

Leedm.B.1979.15.54

An interesting Jurassic Liparoceras sp. (2 Silver stars – Leedm.B.1979.15.54) specimen with crushed inner whorl; from Napton, Warwickshire, England.

Leedm.B.TN133

A stricking little unidentified Jurassic Nautilus sp. (2 Silver stars – Leedm.B.TN133) with mudstone and Sphalerite infill. From Napton, Warwickshire, England.

 

Leedm.B.1979.15.4

A Jurassic Phylloceras heterophyllum (1 Silver star – Leedm.B.1979.15.4) specimen with closely packed ribbing and faint suture lines. From Whitby, North Yorkshire, England.

 

Leedm.B.TN1092

A curious specimen of an Eocene Nautilus imperialis (1 Silver star – Leedm.B.TN1092) featuring two wonderfully preserved chambers and siphuncle.  From Portsmouth, Hampshire, England.

 

Leedm.B.1979.15.35

A well preserved Jurassic Androgynoceras sp. (1 Silver star – Leedm.B.1979.15.35) specimen with distinct ribbing; from North Yorkshire, England.

 

Leedm.B.TN3080

A well preserved Jurassic Cleviceras sp. (1 Silver star – Leedm.B.TN3080) specimen with defined ribbing; from North Yorkshire, England.

Leedm.B.TN5456

A small Cretaceous Euhoplites sp. (1 Silver star – Leedm.B.TN5456) specimen with defined ribbing and nice preservation; from Folkstone, Kent, England.

 

Leedm.B.2011.108

A very good Jurassic Harpoceras falciferum (1 Silver star – Leedm.B.2011.108) specimen exhibiting additional Dactylioceras ammonites within the matrix. From Whitby, North Yorkshire, England.

 

Leedm.B.TN206

A nice Jurassic Hildoceras bifrons (1 Silver star – Leedm.B.TN206) specimen with distinct division of mid-lateral ribbing. From Whitby, North Yorkshire, England.

 

Leedm.B.1979.15.11

A very good Cretaceous Deshayesites sp. (0 Silver stars – Leedm.B.1979.15.11) specimen with interesting morphology. Has no locality data.

 

 

The Bronze specimens

 

Leedm.B.1979.15.121

A less familiar Cretaceous Discohoplites sp. (2 Bronze stars – Leedm.B.1979.15.121) specimen, rare from its locality of Folkstone, Kent, England.

 

Leedm.1979.15.18

A nice Jurassic Aegoceras lataecosta (1 Bronze star – Leedm.B.1979.15.18) specimen from Warwickshire, England.

 

Leedm.B.1998.03.BS

A small and nicely preserved common Jurassic specimen, Promicroceras (1 Bronze star – Leedm.B.1998.03.BS) from Charmouth, Dorset, England.

 

Leedm.B.2014.05.599

A very nice Harpoceras sp. (1 Bronze star – Leedm.B.2014.05.599) specimen, with superb suture lines. From Ilminster, Somerset, England.

 

Leedm.B.TN2810

A very good split nodule specimen containing the common ammonite Dactylioceras commune (1 Bronze star – Leedm.B.TN2810) with nice preservation. From Whitby, North Yorkshire, England.

 

Leedm.B.1979.15.212

A nicely preserved Jurassic Rasenia involuta (0 Bronze stars – Leedm.B.1979.15.212) specimen, with no locality data.

 

 

The review covered 804 specimens, establishing the following summary.

Gold = A truly amazing specimen; Silver = A very good specimen that has great potential; Bronze = A good specimen which can demonstrate a particular feature; Clear = A specimen that has limited visual qualities.

Robert with one of the larger ammonites.

 

3 stars = High scientific importance; 2 stars = Moderate scientific importance; 1 star = Fair scientific importance; 0 stars = Supported by limited or no documentation.

 

 

 

 

 

 

Robert’s summary of the Ammonite collection.

 

Strengths & Weaknesses

The storage facility is excellent and the curator is in the process of allocating specimens to trays in to a well-ordered system.  The collection comprises a number of Palaeozoic cephalopods including some Lower Palaeozoic specimens and a number of Carboniferous examples, including orthocones and Goniatites and two Palaeozoic specimens from Austria.  A number of specimens are well preserved, large and retain good morphological features.  Of note are some excellent Gastrioceras from the Coal Measures preserved in stable pyrite that have mouth-borders.  There are no Devonian or Triassic specimens in the collection.  Presently the trays have accurate contents descriptions (as numbered specimens) but there is no division by taxon or age.  A fair number of specimens (mostly Mesozoic) are unworthy of inclusion and are completely indeterminate.  The bulk of the collection is of Mesozoic ammonites, both Jurassic and Cretaceous from both local areas and locations further afield including ammonites from France. As one might expect there are numerous ammonites from the Yorkshire area.  In particular, there is an extensive and very representative selection of well preserved, complete adult specimens of the genera Hildoceras and Dactylioceras and excellent examples of Harpoceras, Cleviceras and Pseudolioceras from the Lias of Yorkshire.  Unfortunately, the vast majority of specimens have little or no data regarding exact locations and those that do simply state ‘Whitby’. A number of these certainly come from other areas along the coast. Some of these ammonites are of display quality and there is a fine Phylloceras to complement this along with other representative specimens.  The collection includes a number of ammonites of the genus Pleuroceras and some Lower Lias ammonites of rather poor quality.  Surprisingly the Middle and Upper Jurassic of the south of England is rather well represented. At least three excellent specimens of microconch Kosmoceras from Christian Malford, Wiltshire with superb spatulate lappets are present alongside examples from Yorkshire and a small selection of specimens from the Buckman Collection from the Inferior Oolite of Dorset and Somerset including topotypes from Waddon Hill, Stoke Knapp.  There are also two specimens of Stephanoceras presumably from White Nab from a marine band in the Deltaic Middle Jurassic sequence there.  The significance of these specimens is the presence of a biostratigraphically identifiable horizon of ammonites in what is otherwise a deltaic sequence in the Middle Jurassic of Yorkshire.  There is also one superb pathogenic specimen Harpoceras (Leedm.B.1979.15.228).  There are a couple of examples of fragments of giant Portlandian ammonites, but without provenance.

Cretaceous ammonites are represented well but few retain locality information and many are in an advanced state of pyrite decay including those from the Harris Collection.  Most are Aptian or Albian forms, some from Folkestone, Kent including hoplitids of various species, mostly from the Hoplites dentatus and Euhoplites lautus horizons.  Notably the Lower Greensand and some other horizons are poorly represented.  There is a small selection from Cambridgeshire and a few examples from Speeton. There are some good, but poorly localised Hysteroceras, Mortoniceras and a fine Deshayesites along with some miserable fragments of various heteromorphs.

The Upper Greensand and Chalk is again fairly well represented by Schloenbachia, Mantelliceras, Calycoceras and a few very fine intact Scaphites – The labels indicate the Isle of Wight and Lyme Regis but I am of the view that some may come from near Eastbourne, Sussex.

 

Conclusion

There is plenty here for the ammonite specialist to ponder, but its value as a scientific collection is severely limited due to the lack of provenance and stratigraphical precision.

 

The Ammonites, Nautiloids and Cuttlefish,  along with all the other collections are open and free for anyone to view by appointment, just call Leeds Discovery Centre on 0113 3782100 or email discovery.centre@leeds.gov.uk

 

I would like to take this opportunity to thank Robert for three great, fun filled days. The limitless passion and enthusiasm was a joy to behold. “Thank you” for such a wonderful review.