My self seeded foxglove has done this: First question is why; second is-can I save seed-will it breed true?
I find one other photo like yours ( a photographer posted this ). If it is a rare mutation caused by double recessive gene as claimed, you might see it again if you save seed, but the vast majority of seedlings will be normal. If you keep recrossing any plants with the mutation, you might increase the amount of seedlings showing the trait. These types of mutations are discussed here: http://www.academia.edu/1087628/Evo...nces_evidence_from_naturally_occurring_terata It is rather intriguing. I would save the seed.
Such variations occur fairly often, I have encountered them in person myself. All you have to do is search online for photos of Digitalis purpurea and multiple examples of plus sized, deformed flowers at the top of stalks of normal ones appear among the photos of typical plants. I think seed strains have even been named and sold where a high percentage of oversize terminal flowers are expected.
