Abstract
By the removal of the shoot in young maize or pea seedlings 2 opposite effects are produced, (1) a slight increase in the growth of the main root for a few days, (2) a great decrease in the growth of adventitious or secondary roots. By removal of the coleoptile alone (also in young maize seedlings), the growth of adventitious roots is decreased, but to a much less extent. The decrease in growth of lateral roots is probably similar to the decrease in the formation of roots in woody cuttings caused by removal of their buds, as found by van der Lek, and may be due to the lack of some favorable influence that normally comes from the young shoot.