Lewis' and Cunningham's work sets out to establish whether the connection between vegetable growths (fungi) and the diseases characterised by such growths is one of causation or correlation. Having worked as assistants to the sanitary commissioner of India, the researchers focus on the Madura foot-and-hand-disease common on the subcontinent. Fungoid growth of two distinct kinds is characteristic in various stages of the disease. Both the "pale" and the "dark" variety are examined and exemplified on various specimens in order to reveal if they provide a causal factor of the disease.