Snakeshead fritillaries

The snakeshead fritillaries are now beginning to bloom.
When I was an art gallery curator I worked at the Hunterian Art Gallery at the University of Glasgow. In the collection is a series of watercolour drawings of flowers by Charles Rennie Mackintosh, including one of a snakeshead fritillary.
The drawing is probably the best known of his flower drawings, partly because it is one of the more 'finished' ones, but mainly because the checkerboard patterning on the flower connects in with the checkerboard detailing on many of his buildings and pieces of furniture. Most art and architecture students assumed that Mackintosh had either made up, or at least, exaggerated the check effect as a kind of design statement. In fact, Mackintosh's flower drawings were very accurate botanical drawings and it would have been a perfect copy of a flower plucked from a garden on the banks of the Clyde.
Snakeshead fritillaries are a wild flower native to most of Europe, they thrive in grass which is well drained but which doesn't completely dry out. There are spectacular colonies in water meadows down near Cambridge. Their growth is fantastic - first they seem to writhe around on the ground, all whiplash curves, then they straighten themselves up and produce a thin bud which elongates into a snakeshead then opens out into a bell. As well as the purple and white checks there are white and pale purple flowers.