1. Ten cases of benign destructive lesions of bone, either single or multiple, which appear to be identical with what has been described in the recent literature as "eosinophilic or solitary granuloma of bone", are presented. All were in children under twelve years of age.

2. Roentgenographically, single lesions simulated bone cyst, osteomyelitis, or malignancy. Multiple lesions suggested multiple myeloma or malignancy, but in the roentgenograms were indistinguishable from Hand-Schüller-Christian disease.

3. There was little general illness associated with the disease in most instances. The symptoms were attributable mainly to the local process.

4. The histopathology presented variations from "eosinophilic granuloma" to "lipogranuloma", which is interpreted as identical with certain stages of Hand-Schüller-Christian disease.

5. Ordinarily, the lesions have healed quite promptly after roentgen radiation, and, on occasion, after curettage.

6. Nine of the ten patients were well on a follow-up examination three to ten years after they were first observed. One had died, the details of which case are unknown.

7. As suggested by one of the authors in a previous communication, eosinophilic or solitary granuloma is not a distinct new entity, but a variant of the basic process of which the clinical pictures known as Hand-Schüller-Christian and Letterer-Siwe diseases are other examples.

8. Despite the excellent prognosis in nine of the ten patients in this group, in which the recognized lesions were restricted to bone, if the suggested relationship to Hand-Schüller-Christian disease exists, the prognosis given in an individual case should be guarded, and the possibility of visceral lesions should be kept in mind.