IN addition to the legumes, a number of non-legumes are reported to possess nodules on their roots. Some of these nodules are caused by bacteria while others are caused by Actinomyces. It may be interesting to mention that bacterial nodules are also found on the roots of the Zygophyllaceae. Among the plants which have been observed to possess such nodules are: Zygophyllum album, Z. coccineum, Z. decumbens, Z. simplex (Fig. 1), Fagonia arabica and Tribulus alatus. They all grow in the poor sandy soils of the Egyptian deserts.