SINCLAIR STAMMERS / Light photomicrograph of Blue green algae / Cyanobacteria (Nostoc sp) capable of nitrogen fixation, and used for soil enrichment especially with rice cultivation. The long filaments are composed of in...

Alex Hyde / Freshwater grapes (Nostoc sp.), a blue-green algae or cyanobacteria, found in a shallow freshwater pool on an area of limestone pavement. Gait Barrows National Nature Reserve, Lancashire, UK. Septembe...

Alex Hyde / Freshwater grapes (Nostoc sp.), a blue-green algae or cyanobacteria, found in a shallow freshwater pool on an area of limestone pavement. Gait Barrows National Nature Reserve, Lancashire, UK. Septembe...

Alex Hyde / Freshwater grapes (Nostoc sp.), a blue-green algae or cyanobacteria, found in a shallow freshwater pool on an area of limestone pavement. Gait Barrows National Nature Reserve, Lancashire, UK. Septembe...

Alex Hyde / Shallow pool on an area of limestone pavement containing Freshwater grapes (Nostoc sp.), a blue-green algae or cyanobacteria. Gait Barrows National Nature Reserve, Lancashire, UK. September.

Alex Hyde / Shallow pool on an area of limestone pavement containing Freshwater grapes (Nostoc sp.), a blue-green algae or cyanobacteria. Gait Barrows National Nature Reserve, Lancashire, UK. September.

Nick Upton / Star jelly (Nostoc commune) on rotting log, GWT Lower Woods reserve, Gloucestershire, UK, October.

Will Watson / Star Jelly (Nostoc commune) a blue-green alga, on base of a pond, Brockhall Quarry, Herefordshire, England, July.

SINCLAIR STAMMERS / Blue green algae / cyanobacteria (Nostoc sp) occurring naturally as nodules in a water-filled depression in Carboniferous Limestone at The Burren in Western Ireland. These nodules are roughly the size...