Peter Lewis / Snakes head fritillary (Fritillaria meleagris) flowering with Dandelions in meadow Cricklade, Wiltshire, England, UK, April.

Heather Angel / Snake's head fritillary (Fritillaria meleagris), view into flower with linear green nectaries. In cultivation, Surrey, England, UK. April.

Mike Read / Snakeshead fritillary (Fritillaria meleagris) growing in garden lawn. Corfe Mullen, Dorset, England, UK. April.

Adrian Davies / Snakeshead fritillary (Fritillaria meleagris), rare double white variety. Beech Hill, Berkshire, England, UK. April.

Chris Mattison / Snakeshead Fritillary (Fritillaria meleagris) Monmouthshire, Wales, UK. March.

Ann & Steve Toon / Wildlife Trust volunteers surveying Snakeshead fritillary (Fritillaria meleagris) flowers. Iffley Meadow, Oxford. April.

Ann & Steve Toon / Snakeshead fritillary (Fritillaria meleagris) flower, Iffley Meadow, Oxford, April

Ann & Steve Toon / Snakeshead fritillaries (Fritillaria meleagris) in Iffley Meadow, Oxford. April.

Loic Poidevin / Snake's head fritillary (Fritillaria meleagris) flowering in marsh, Audubon Reserve, West France, France, March

MYN / Marc Pihet / Snake's head fritillary (Fritillaria meleagris) in flower, Maine-et-Loire, France, April, meetyourneighbours.net project

MYN / Marc Pihet / Snake's head fritillary (Fritillaria meleagris) in flower, Maine-et-Loire, France, April, meetyourneighbours.net project

MYN / Marc Pihet / Snake's head fritillary (Fritillaria meleagris) in flower, Maine-et-Loire, France, April, meetyourneighbours.net project