Fossil bryozoan collection (Bryozoa)

Bryozoans are small, diverse, colonial organisms that preserve exceptionally well as secretions of hard calcareous walls or as borings within hard carbonate substrates. 

The Natural History Museum holds the best collection of fossil bryozoans in the world, with over 5,000 type and figured specimens.

The collection has about 750,000 specimens, making it one of the most numerous in the Palaeontology Department.

The value of the collection is enhanced by a specialist library.


Geological range:

The full geological range of each group of bryozoans except the Phylactolaemata is represented:

  • the class Gymnolaemata, with the following orders:
    • Cheilostomata (Jurassic to Recent)
    • Ctenostomata (Ordovician to Recent)
  • the class Stenolaemata, with the following orders:
    • Cryptostomata (Ordovician to Triassic)
    • Cyclostomata (Ordovician to Recent)
    • Cystoporata (Ordovician to Triassic)
    • Fenestrata (Ordovician to Permian)
    • Trepostomata (Ordovician to Triassic)
Geographical range:

The collection is representative of all continents.

  • Miocene fossil bryozoans annoted for Sir Charles Lyell
    Historic collections containing fossil bryozoans

    The Museum cares for many important collections linked to major characters in the history of bryozoan palaeontology. Find out some of the highlights.

  • Scanning electron micrograph of Wilbertopora woodwardi (Brydone)
    Research visitor facilities

    More than 50,000 scanning electron microscope images of bryozoans are available to researchers visiting this collection. Other available facilities include a visitor's room and specialist library. Learn more.

Collections management and curation


The fossil bryozoan collection is divided:

  1. stratigraphically
  2. with further geographical sub-divisions:
    • Britain
    • Europe
    • the rest of the world

Within this, the specimens are arranged alphabetically by genus and then species. There is often a large amount of unsorted material at the end of each section.

There is a small amount of fossil material retained in historic collections and in collections related to publications. These will eventually be reintegrated back into the collections.


Specimens are kept in drawer units:

  • usually boxed
  • sometimes stored in tubes
  • sometimes attached to cards, if older


  • Small specimens are placed in cavity slides. Many of these are stored in 3 separate cabinets.
  • There are 2 cabinets containing thin sections.

Each draw is labelled with stratigraphic information. Often there are additional details which can vary but include:

  • geographic location (country/region)
  • collector name
  • taxonomic information

Most of the collection is well provenanced and original labels are often retained with the specimens.

Green spots indicate that specimens are:

  • holotype
  • lectotype
  • syntype
  • figured in publications

Generally, red spots indicate that specimens are:

  • mentioned in publications
  • paratype

Publication data is indicated on the specimen label.


Fossil bryozoan specimens can be found in 2 locations in London in the Natural History Museum:

  • Most are stored in the Palaeontology Department.
  • Some are on display in the Earth Lab and in the Fossils from Britain gallery.