Three species of Stemphylium, which have been isolated from agricultural seeds, are described and illustrated: S. botryosum Wallr., S. sarcinaeforme (Cav.) Wilts., and S. consortiale (Thüm.) n. comb. S. sarcinaeforme has been found only on seeds of red clover; the other two species occur on a wide variety of seeds. The perfect stage of S. botryosum is Pleospora herbarum (Pers.) Rabenh. but the perfect stages of the other two species are unknown.