Observations on the Swollen Lateral Roots of the Cyperaceae

Summary A swollen and markedly hairy type of lateral root in the Cyperaceae is described which closely resembles the proteoid roots of certain Proteaceae. In both cases the existence of some biological causal agent outside the root tissue is indicated and the young swollen laterals of Carex flacca, examined with light and electron microscopy, exhibited no endophytes. These roots form extensive mats in the surface soil and the idea is advanced that they may play some particular role in the absorption of nutrients.