Beatrix did get into mischief. The girl had the mind of a scientist and the eyes of an artist. She was fascinated by the natural history section of the South Kensington museum, her interest fuelled by the plants and animals seen on holidays in Scotland and the Lake District.

One became an obsession. For 13 years she studied fungus, research that swept her on to a scientific battleground and ultimately made her the victim of a shameful blunder. In 1869 Simon Schwendener, a Swiss botanist, proposed that lichens were symbiotic communes of fungi and algae. He was ridiculed. His name became an insult. The theory was out of kilter with a Victorian mindset that divided the natural world into neat and competing categories.

Beatrix, however, was a Schwendenerist. All her work, collecting, identifying and dissecting specimens, proved he was right. Now in her late twenties she longed to make a proper contribution to science. But would anyone listen to a woman? Her favourite uncle, Sir Henry Roscoe, a chemist, tried to help. In 1897 he presented a ground-breaking paper by Beatrix on the germination of fungal spores to the Linnaean Society in London. In the same grand rooms, 40 years earlier, Charles Darwin had announced the theory of evolution.

Beatrix was not actually in the building. Women were barred from attending meetings, let alone addressing the eminent male biologists. And her discoveries fell by the wayside, with no one even keeping a record of the gathering. This was enough for Beatrix, a shy woman, disgusted by what she sarcastically called the “grown-up world of science”. She turned instead to children’s books. So we have Peter Rabbit, when we could have had an eminent female biologist. It was 100 years before the Linnaean Society said sorry.