A description is provided for Erwinia stewartii[Pantoea stewartii subsp. stewartii]. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Zea mays, Euchlarna mexicana and Tripsacum dactyloides. Artificial inoculation has been successful on Coix lachryma-jobi, Euchlaena perennis, Schlerachne punctata and Setaria lutescens[Setaria pumila]. Poos (19: 467), using insects, showed that various common plants could act as symptomless hosts. DISEASE: Stewart's disease or bacterial wilt of maize. A vascular disease in which the vessels become plugged with bright yellow slime. If stems are cut across the slime will often exude. Affected plants are dwarfed, have pale stripes on the leaves, and may have prematurely developed tassels which wither and die before the rest of the plant. Some plants wilt progressively and die, others survive and bear seed which may be infected. GEOGRAPHICAL DISTRIBUTION: Mainly in North and Central America, but has also been reported from Italy, Poland, Rumania, U.S.S.R., Yugoslavia, China, Peru and, recently, from Thailand (45, 3508). (CMI Map 41, ed. 2, 1965). TRANSMISSION: Mainly by insects. In the United States spread of the disease is chiefly due to Chaetocnerna pulicaria, which conveys the bacteria from leaf to leaf and also retains the bacteria during hibernation. After mild winters this insect is responsible for the early infection of much young maize. Various other insects have been shown either to harbour the pathogen or to be able to transmit it. These include the larvae of Diabrotica longicornis and Phorbia cilicrura[Delia platura] which can carry the bacteria from root to root and from infected to healthy seed (12: 364; 16: 167). The bacteria are also carred into new areas in infected seed.