Lathyrus vernus (L.)Bernh. Papilionaceae previously Orobus vernus L. (Linnaeus, 1753) Spring vetchling. Distribution: Europe to Siberia. The seeds of several Lathyrus species are toxic, and when eaten cause a condition called lathyrism. The chemical diaminoproprionic acid in the seeds causes paralysis, spinal cord damage, aortic aneurysm, due to poisoning of mitochondria causing cell death. Occurs where food crops are contaminated by Lathyrus plants or where it is eaten as a 'famine food' when no other food is available. It is the Orobus sylvaticus purpureus vernus of Bauhin (1671) and Orobus sylvaticus angustifolius of Parkinson (1640) - who records that country folk had no uses for it. Photographed in the Medicinal Garden of the Royal College of Physicians, London.