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.



Type specimens





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.


Red algae (Rhodophyta) 120,000

Brown algae (Phaeophyceae) 50,000

Marine green algae (Chlorophyta) 35,000

Freshwater and terrestrial green algae (Charophyta) 18,000

Cyanobacteria (Cyanophyta) 8,000

Other groups (including euglenoids and xanthophytes) 1,000

Type specimens

Red algae (Rhodophyta) 5,500

Brown algae (Phaeophyceae) 2,000

Marine green algae (Chlorophyta) 1,500

Freshwater and terrestrial green algae (Charophyta) 800

Cyanobacteria (Cyanophyta) unknown

Other groups (including euglenoids and xanthophytes) 10

Material type

Herbarium sheets 230,000

Boxed collection 4,000

Microscope slides marine 24,000

Microscope slides fresh 10,000

Liquid (spirit) marine 6,000

Liquid (spirit) fresh 3,000

Unincorporated collections around 15,000

Historical bound volumes – around 80

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).




W H Harvey

J Hooker

Dawson Turner

E Batters

F Schmitz

A D Cotton

M Foslie

W and G S West

E M Holmes

J Lightfoot

Maze and Schramm

FE Fritsch

K Drew

A W Griffiths

G Dickie

A Hassall

J Ralfs

W Joshua

E Jenner

G O Allen

H and J Groves

G R Bullock-Webster

T B Blow

Expeditionary voyages

JA Brodie

YM Chamberlain

WF Farnham

DM John

LM Irvine

CA Maggs

JH Price

I Tittley

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.

Early collections


New Zealand

South Africa

North America

South America

Falkland Islands

Contemporary collections

West Africa


United Arab Emirates


Looking for a specimen?

The algae collection is being digitised

Any Questions?

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


Collections on the move

Access to some collections will be affected as we prepare for the move to our new collections, science and digitisation centre.

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.