Pericambium, or, as it is now termed, pericycle, a ring of tissue surrounding the stele (q.v.) in roots or stems. It may be homogeneously composed of thin-walled parenchyma (q.v.), or it may be heterogeneous, containing a circle, or detached strands, of stereom (q.v.), either sclerenchymatous or collenchymatous. In it the lateral branches of the root originate.