The disease is owing to the development of a fungus of the order of moulds (mucedines); now know as Peronospora infestans , Montague; the leaf is first attacked. Authorities. 1 , Mure, Pathogénésie Brésilienne, proving by Van Dyck; 2 , same, proving by Jolly; 3 , same, proving by Mrs. A. G., aged twenty-six; 4 , Reddie, Edin. Med. and Surg. Journ., 1833, p. 384, effects of eating diseased potatoes (child had recently suffered from scarlatina); 5 , same, a boy aged six, same family, fatal result; 6 , same, child aged four, same family, fatal result; 7 , Banks, Dublin Med. Journ., 1846, p. 267, a man and three children poisoned by diseased potatoes (boiled); 8 , O'Brien, Dublin Hosp. Gaz., January, 1846, effects of eating diseased potatoes; 9 , McCormack, Lancet, 1846, 2, 91, effects in a girl of nineteen, of eating diseased potatoes "for a long time."