Algae collections

Seaweed laid out flat on a white background

The seaweed Delesseria sanguinea.

The Museum's collection of algae is one of the largest in the world, with more than a quarter of a million specimens from around the globe.

Algae specimens account for about five per cent of the Museum's botanical collections. The diatom collections are curated separately.


The algae collections number around 400,000 specimens. The main algal groups represented here are:

  • red, green and brown seaweeds
  • freshwater algae including charophytes
  • cyanobacteria.

The algae collections include:

  • some of the earliest specimens held in the Museum, dating back to the seventeenth century
  • expanding contemporary collections
  • around 10,000 algal type specimens.

Major collections

The earliest algae specimens are in the Sir Hans Sloane Herbarium, the Museum's founding collection, with material dating from the early 1600s to the mid-1700s. 

Of particular note are the collections of Adam Buddle, which are incorporated here and include seaweed specimens collected from UK shores in the 1690s.

Recent important collections

In 1970 the algae collections at the Museum and the Royal Botanical Gardens, Kew were amalgamated. The size of the Museum’s algae collection doubled, dramatically increasing the number of type and historically important specimens.

Recent collections are the vouchers for field research and/or published revisions and floras (such as the Seaweeds of the British Isles series).

Country of origin

The herbarium has a global coverage. The UK is particularly well represented, with a timeline of specimen data going back over 250 years.

Looking for a specimen?

The algae collection is being digitised


Jo Wilbraham

Any questions?

If you would like to use any specimens for research, please get in touch

Collections on the move

We have set out on an ambitious programme to develop a new science and digitisation centre. As we prepare for the move, access to some collections will be affected. 

Find out more and sign up to our newsletter to receive updates on changes to collections access, relevant news and opportunities to get involved.

Accessing the collections

Scientists and collections management specialists can visit the collections and borrow specimens for research.

Collections management

Our duty is to provide a safe and secure environment for all of our collections.