1. A family of six generations, consisting of 114 members affected by epiphysial dysplasia of the lower extremities, is described.

2. Twenty-two males and twenty-three females were affected, while thirty-two males and thirty females were unaffected. Seven members of the family could not be traced.

3. Variations from Fairbank's description of dysplasia epiphysialis multiplex are discussed. In the family here reported the lower limbs only were affected and the severity of the disease was very variable.

4. Long term follow-up studies are presented.