In recent years several investigators have described the histologic findings made in the external eye muscles in biopsies or necropsies in cases of chronic progressive external ophthalmoplegia.2,4,7,8,12,13 The authors cited agree that the changes are of the type usually seen in skeletal muscles in progressive muscular dystrophy, and they are of the opinion that chronic progressive external ophthalmoplegia is closely related to progressive muscular dystrophy and represents a particular type of this disease with preponderant or selective affection of the extrinsic eye muscles. Further support for this view is found in the concomitant occurrence of dystrophic changes in skeletal muscles in some cases.4,7,8 The previously generally accepted opinion that progressive external ophthalmoplegia is primarily an affection of the nuclei of the eye muscle nerves appears to rest on insufficient evidence, as discussed by Kiloh and Nevin,7 Schwarz and Liu,13 and Adams, Denny-Brown, and Pearson.1 The