The purpose of the present invention is to prevent a longitudinal feed member from interfering with a pot part when longitudinal feed members are linked between left and right endless chains and come in between pot parts, thereby preventing seedling trays from being squashed and preventing the longitudinal feed member from skipping one row. A longitudinal delivery device (30) for a transplanter (10) that longitudinally delivers seedling trays (20), wherein a plurality of pot parts (20a) that accommodate cell plug seedlings are disposed longitudinally and horizontally, to a transplanting unit (3) is provided with left and right drive sprockets (34), left and right endless band guides (35), left and right endless chains (40, 40) that are wound around the drive sprockets (34) and the endless band guides (35), and a plurality of longitudinal feed members (45, 45...) for holding the seedling trays by means of the left and right endless chains (40, 40). The longitudinal feed members (45, 45...) are disposed so as to be offset to the inside from the center in the direction of vertical thickness of the endless chains (40).