"Toimaru" were organizations specialized in transport, warehousing and commission sales, which based themselves in cities by the rivers and ports where nengumai (rice paid as land tax) was unloaded.
問丸（といまる）は、年貢米の陸揚地である河川・港の近郊の都市に居住し、運送、倉庫、委託販売業を兼ねる組織。