SCOTLAND: The Big Picture / Mermaid purse, shark egg, Dogfish (Scyliorhinus caniculus) Loch Creran, west coast of Scotland, UK, October.

Heidi & Hans-Juergen Koch / Greater Spotted Dogfish (Scyliorhinus stellaris) embryo in mermaid's purse egg capsule, native to Atlantic and Mediterranean

Alex Hyde / Nursehound dogfish (Scyliorhinus stellaris) empty egg cases / mermaid's purse. Anglesey, Wales, UK. December.

Alex Hyde / Nursehound dogfish (Scyliorhinus stellaris) empty egg cases / mermaid's purse. Anglesey, Wales, UK. December.

Alex Hyde / Spotted ray (Raja montagui) egg case or mermaid's purse washed up on strandline. Anglesey, Wales, UK. December.

Alex Hyde / Nursehound dogfish (Scyliorhinus stellaris) empty egg cases / mermaid's purse and a single much samller eggcase from a Smallspotted catshark (Scyliorhinus canicula). Anglesey, Wales, UK. December.

MYN / Dimitris Poursanidis / The mermaid's purse, an egg capsule of a shark, beached material, Heraklion, Crete, Greece meetyourneighbours.net project

Adrian Davies / A Mermaid's purse, the egg case of Dogfish (Scyliorhinus canicula) lying on a rock, Prawle Point, Devon, England, July.

Adrian Davies / A Mermaid's purse, the egg case of Dogfish (Scyliorhinus canicula) lying on Brown algae (Fucus), Prawle Point, Devon, England, UK, July.

Adrian Davies / A Mermaid's purse, the egg case of Dogfish (Scyliorhinus canicula) lying on shingle, Prawle Point, Devon, England, July.

Nick Upton / Yolk and developing embryo visible in Mermaid's purse egg case of Lesser spotted catshark / Dogfish (Scyliorhinus canicula) entangled with Coralweed (Corallina officinalis) in a rockpool. Rhossil...

Nick Upton / Yolk and developing embryo visible in Mermaid's purse egg case of Lesser spotted catshark / Dogfish (Scyliorhinus canicula) entangled with Coralweed (Corallina officinalis) in a rockpool. Rhossil...